Astronomik 6nm Narrowband Filters
The 6nm Astronomik Narrowband-Emissionline filters are generally the best choice and our clear recommendation for any ambitious astrophotographer – regardless of whether you use a modern DSLR or system camera or a dedicated CMOS astro camera.
The Astronomik Narrowband-Emissionline filters with a Full-Width-Half-Maximum (FWHM) of 6nm are ideal for astrophotography of faint objects in star-crowded regions of the milky way. Compared to a 12nm filter, a 6nm filter typically reduces the number of stars in the image by half. Even bright stars appear smaller and nebulae stand out more clearly
The 6nm filters are particularly well suited if you are using a modern, cooled camera with very low dark current or taking pictures from a location with severe light pollution. The strong suppression of the sky background allows you to use longer exposure times and achieve detailed and high-contrast images.
All our 6nm Narrowband-Emissionline filters are also available as MaxFR-Filters for use with fast optical systems.
In addition, the 6nm filters are available in all standard sizes, as we offer mounted filters in threaded cells, filters without threads in a protective ring as well as Clip-Filters for use in modern DSLR and system cameras.
Astronomik MFR and MaxFR coating
The MFR coating ensures that Astronomik Narrowband-Emissionline filters can be used with almost all instruments. This means you don’t have to buy different filters for different focal ratios, as it is the case with most competitors. Unlike filters from other manufacturers, which often require special “high-speed” versions, Astronomik’s MFR filters keep their transmission properties with both fast and slow optics.
Astronomik has developed the MaxFR coating for extremely fast optical systems such as the Celestron RASA and Takahashi Epsilon Astrographs.
Both the Astronomik MFR and MaxFR coatings offer needle-sharp stars, extremely high contrast, minimized stray light, no halos and the best possible blocking across the entire spectral range from UV to IR.

Astronomik HSO 6nm Filterset 36mm
Our popular Astronomik Narrowband-Emissionline filters are also available as a budget-friendly HSO filter set. This filter set offers an excellent opportunity to create false-color emission line images similar to those produced by the Hubble Space Telescope.Detailed insights into each Astronomik Narrowband-Emissionline filter’s specific applications can be found here: H-alpha, SII and OIII.The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Difference between Astronomik 12nm and 6nm filtersThe choice between 12nm and 6nm Full-Width-Half-Maximum (FWHM) filters depends on your imaging conditions and camera type. There is no universal "best" option - each FWHM serves a specific purpose.The 12nm Astronomik Narrowband-Emissionline filters are better suited for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current or if you are observing from suburban or dark-sky locations. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they generally show more guiding stars compared to the 6nm filter.In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the FWHM does not bring out more details in the object. The 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way, as they typically halve the number of stars in the image compared to the 12nm filter. They are also suitable if you have a camera with very low dark current or if you are observing from a location with extreme light pollution.The Astronomik MFR coatingThe Astronomik MFR coating gives you the best out-of-band blocking over the entire wavelength range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.Technical dataGuaranteed transmission of more than 90% (12nm and 6nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm) at the H-alpha line Guaranteed transmission of more than 90% (12nm and 6nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm) at both SII linesGuaranteed transmission of more than 90% (12nm) and 88% (6nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm) at the major OIII lineGlass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik HSO 6nm Filterset 2" (M48)
Our popular Astronomik Narrowband-Emissionline filters are also available as a budget-friendly HSO filter set. This filter set offers an excellent opportunity to create false-color emission line images similar to those produced by the Hubble Space Telescope.Detailed insights into each Astronomik Narrowband-Emissionline filter’s specific applications can be found here: H-alpha, SII and OIII.The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Difference between Astronomik 12nm and 6nm filtersThe choice between 12nm and 6nm Full-Width-Half-Maximum (FWHM) filters depends on your imaging conditions and camera type. There is no universal "best" option - each FWHM serves a specific purpose.The 12nm Astronomik Narrowband-Emissionline filters are better suited for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current or if you are observing from suburban or dark-sky locations. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they generally show more guiding stars compared to the 6nm filter.In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the FWHM does not bring out more details in the object. The 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way, as they typically halve the number of stars in the image compared to the 12nm filter. They are also suitable if you have a camera with very low dark current or if you are observing from a location with extreme light pollution.The Astronomik MFR coatingThe Astronomik MFR coating gives you the best out-of-band blocking over the entire wavelength range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.Technical dataGuaranteed transmission of more than 90% (12nm and 6nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm) at the H-alpha line Guaranteed transmission of more than 90% (12nm and 6nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm) at both SII linesGuaranteed transmission of more than 90% (12nm) and 88% (6nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm) at the major OIII lineGlass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik SII 6nm 2" (M48)
The Astronomik SII filter is ideal for imaging nebulae showing sulfur emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 671.7nm and 673nm (SII lines) and the sky background. The Astronomik SII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 671.7nm and 673nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik SII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at both SII lines Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik H-alpha 6nm 2" (M48)
The Astronomik H-alpha filter is ideal for imaging hydrogen nebulae from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background. The Astronomik H-alpha filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 656nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik H-alpha 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at the H-alpha line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik HSO 6nm Filterset 1,25" (M28,5)
Our popular Astronomik Narrowband-Emissionline filters are also available as a budget-friendly HSO filter set. This filter set offers an excellent opportunity to create false-color emission line images similar to those produced by the Hubble Space Telescope.Detailed insights into each Astronomik Narrowband-Emissionline filter’s specific applications can be found here: H-alpha, SII and OIII.The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Difference between Astronomik 12nm and 6nm filtersThe choice between 12nm and 6nm Full-Width-Half-Maximum (FWHM) filters depends on your imaging conditions and camera type. There is no universal "best" option - each FWHM serves a specific purpose.The 12nm Astronomik Narrowband-Emissionline filters are better suited for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current or if you are observing from suburban or dark-sky locations. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they generally show more guiding stars compared to the 6nm filter.In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the FWHM does not bring out more details in the object. The 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way, as they typically halve the number of stars in the image compared to the 12nm filter. They are also suitable if you have a camera with very low dark current or if you are observing from a location with extreme light pollution.The Astronomik MFR coatingThe Astronomik MFR coating gives you the best out-of-band blocking over the entire wavelength range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.Technical dataGuaranteed transmission of more than 90% (12nm and 6nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm) at the H-alpha line Guaranteed transmission of more than 90% (12nm and 6nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm) at both SII linesGuaranteed transmission of more than 90% (12nm) and 88% (6nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm) at the major OIII lineGlass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik OIII 6nm 36mm
The Astronomik OIII filter is ideal for imaging nebulae showing oxygen emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 496nm and 501nm (OIII lines) and the sky background. The Astronomik OIII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 496nm and 501nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik OIII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm) and 88% (6nm and 4nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm and 4nm) at the major OIII line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik OIII 6nm 1,25" (M28,5)
The Astronomik OIII filter is ideal for imaging nebulae showing oxygen emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 496nm and 501nm (OIII lines) and the sky background. The Astronomik OIII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 496nm and 501nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik OIII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm) and 88% (6nm and 4nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm and 4nm) at the major OIII line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik OIII 6nm 2" (M48)
The Astronomik OIII filter is ideal for imaging nebulae showing oxygen emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 496nm and 501nm (OIII lines) and the sky background. The Astronomik OIII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 496nm and 501nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik OIII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm) and 88% (6nm and 4nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm and 4nm) at the major OIII line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik SII 6nm 36mm
The Astronomik SII filter is ideal for imaging nebulae showing sulfur emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 671.7nm and 673nm (SII lines) and the sky background. The Astronomik SII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 671.7nm and 673nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik SII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at both SII lines Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik H-alpha 6nm 36mm
The Astronomik H-alpha filter is ideal for imaging hydrogen nebulae from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background. The Astronomik H-alpha filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 656nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik H-alpha 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at the H-alpha line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik HSO 6nm Filterset 50mm
Our popular Astronomik Narrowband-Emissionline filters are also available as a budget-friendly HSO filter set. This filter set offers an excellent opportunity to create false-color emission line images similar to those produced by the Hubble Space Telescope.Detailed insights into each Astronomik Narrowband-Emissionline filter’s specific applications can be found here: H-alpha, SII and OIII.The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Difference between Astronomik 12nm and 6nm filtersThe choice between 12nm and 6nm Full-Width-Half-Maximum (FWHM) filters depends on your imaging conditions and camera type. There is no universal "best" option - each FWHM serves a specific purpose.The 12nm Astronomik Narrowband-Emissionline filters are better suited for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current or if you are observing from suburban or dark-sky locations. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they generally show more guiding stars compared to the 6nm filter.In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the FWHM does not bring out more details in the object. The 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way, as they typically halve the number of stars in the image compared to the 12nm filter. They are also suitable if you have a camera with very low dark current or if you are observing from a location with extreme light pollution.The Astronomik MFR coatingThe Astronomik MFR coating gives you the best out-of-band blocking over the entire wavelength range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.Technical dataGuaranteed transmission of more than 90% (12nm and 6nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm) at the H-alpha line Guaranteed transmission of more than 90% (12nm and 6nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm) at both SII linesGuaranteed transmission of more than 90% (12nm) and 88% (6nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm) at the major OIII lineGlass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik SII 6nm 1,25" (M28,5)
The Astronomik SII filter is ideal for imaging nebulae showing sulfur emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 671.7nm and 673nm (SII lines) and the sky background. The Astronomik SII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 671.7nm and 673nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik SII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at both SII lines Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik HSO 6nm Filterset 31mm
Our popular Astronomik Narrowband-Emissionline filters are also available as a budget-friendly HSO filter set. This filter set offers an excellent opportunity to create false-color emission line images similar to those produced by the Hubble Space Telescope.Detailed insights into each Astronomik Narrowband-Emissionline filter’s specific applications can be found here: H-alpha, SII and OIII.The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Difference between Astronomik 12nm and 6nm filtersThe choice between 12nm and 6nm Full-Width-Half-Maximum (FWHM) filters depends on your imaging conditions and camera type. There is no universal "best" option - each FWHM serves a specific purpose.The 12nm Astronomik Narrowband-Emissionline filters are better suited for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current or if you are observing from suburban or dark-sky locations. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they generally show more guiding stars compared to the 6nm filter.In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the FWHM does not bring out more details in the object. The 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way, as they typically halve the number of stars in the image compared to the 12nm filter. They are also suitable if you have a camera with very low dark current or if you are observing from a location with extreme light pollution.The Astronomik MFR coatingThe Astronomik MFR coating gives you the best out-of-band blocking over the entire wavelength range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.Technical dataGuaranteed transmission of more than 90% (12nm and 6nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm) at the H-alpha line Guaranteed transmission of more than 90% (12nm and 6nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm) at both SII linesGuaranteed transmission of more than 90% (12nm) and 88% (6nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm) at the major OIII lineGlass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik H-alpha 6nm Clip-Filter Sony alpha 7
The Astronomik H-alpha filter is ideal for imaging HII regions from both light-polluted and dark observation sites. The Astronomik H-alpha filter significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background, allowing for long exposure times for deep and high-contrast images. The filter blocks the emission lines of high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, the maxima of typical LED lights, most lines of natural airglow, as well as most of the distracting moonlight. The Astronomik H-alpha filter effectively blocks all unwanted light from wavelengths other than 656nm, from ultraviolet (UV) to infrared (IR). The Astronomik H-alpha filter MUST NOT BE USED for solar observation! Difference between Astronomik 12nm, 6nm and 4nm filters The choice between 12nm, 6nm and 4nm Full-Width-Half-Maximum (FWHM) filters depends on your imaging conditions and camera type. There is no universal “best” option - each FWHM serves a specific purpose. The 6nm Astronomik Narrowband-Emissionline filters are usually the best choice for astrophotography. They are ideal for imaging faint objects in star-crowded regions of the milky way, as they typically halve the number of stars in the image compared to 12nm filters, greatly simplifying image processing. The 6nm Narrowband-Emissionline filters are the first choice, especially if you are using a CMOS astro camera or a modern system camera with very low dark current, or if you are observing from a location with strong light pollution. The excellent suppression of the sky background allows you to use long exposure times. The 6nm filters provide a dark background and outstanding details of faint nebulae. The Astronomik MFR coating Both the Astronomik MFR and MaxFR coatings offer extremely high contrast, minimized stray light, no halos and needle-sharp stars. In addition, they provide the best possible blocking across the entire spectral range from UV to IR. 6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/15 without visible performance loss. Clip-Filters for Sony Alpha 7 and Alpha 9 cameras Sony Alpha 7 and Alpha 9 cameras are an excellent choice for astrophotography. With Astronomik Clip-Filters, you can use our full range of filters with your camera to capture stunning images. Whether paired with a camera lens or a telescope, our Clip-Filters ensure maximum image quality and performance from your setup. The Astronomik Clip-Filters offer a number of practical advantages that make them an ideal choice for astrophotographers: Installing and removing the Astronomik Clip-Filter is very quick and easy and requires no extra tools or modifications to the camera body. They can be changed at any time, even at night. All lens functions, such as focus, aperture, and image stabilization remain fully functional. The Astronomik Clip-Filters are held securely in place without stressing the high-quality glass. The Astronomik Clip-Filters are designed and optimized for use with both standard camera lenses and telescopes. Through the Astronomik Clip-Filters, we were able to solve several common issues faced by astrophotographers: Large filters for large camera lenses are very expensive. Using a filter holder between the camera body and the lens prevents focusing to infinity. For very fast telescopes (low f-number) like the Vixen R200SS or the Takahashi “Epsilon” astrograph, a filter drawer or filter wheel can not be used because the distance to the corrector lenses would be changed. Long exposure times lead to dust settling on the camera’s sensor chip. Due to the very tight Sony bayonet and the limited space inside the camera, the Astronomik Sony Alpha 7 Clip-Filters cause a minimal obstruction in the corners. But this can be easily corrected by flatfielding. Additionally, all Astronomik Sony Alpha 7 Clip-Filters serve as an excellent dust shield, protecting the sensor during long exposures. If you only need a dust shield without filtering effects, the Astronomik MC-Clear Sony Alpha 7 Clip-Filter is the right choice. NOTE: Please store the Clip-Filter in the supplied storage box and do not leave it in the camera permanently. Use Astronomik filters for your Sony Alpha 7 or Alpha 9 camera and enjoy marvelous images with ultra-light equipment! Compatible Sony Alpha cameras Model Compatibility Sony Alpha 7 Sony Alpha 7 Mk II Sony Alpha 7 Mk III Sony Alpha 7 Mk IV Sony Alpha 7 Mk V Sony Alpha 7C Sony Alpha 7C Mk II Sony Alpha 7CR Sony Alpha 7R Sony Alpha 7R Mk II Sony Alpha 7R Mk III Sony Alpha 7R Mk IV Sony Alpha 7R Mk V Sony Alpha 7S Sony Alpha 7S Mk II Sony Alpha 7S Mk III Sony Alpha 9 Sony Alpha 9 Mk II Sony Alpha 9 Mk III Sony Alpha 58 Sony Alpha 68 Sony Alpha 77 (all variants) Sony Alpha 99 (all variants) Sony Alpha 6000 Sony DSLR cameras with A-bayonet Non-compatible lenses Model Compatibility Sigma 14mm F1.4 DG DN Art Sony FE 12-24mm f2.8 GM (SEL1224GM) Technical Data Guaranteed transmission of more than 90% at the H-alpha line (656nm) Typical transmission of 93% at the H-alpha line Full-Width-Half Maximum (FWHM): 6nm Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters) Finely polished optical glass, free of any striae, residual stresses, and bubbles Extremely scratch-resistant and durable coating Completely resistant against high humidity and aging effects Astronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters) Parfocal with other Astronomik filters Diffraction-limited Optimized spectral windows Delivered in a high-quality, long-lasting filter box Made in Germany Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Thanks to the high-precision machining of the glas substrate, all Astronomik filters are parfocal. The wedge errors are far below all common tolerances. Therefore, all issues concerning focal distances and the exact alignment of images from each color channel are effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR and MaxFR coatings are designed for optimal performance across a wide range of focal ratios of the optics used. Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios for best performance of that specific filter.

Astronomik H-alpha 6nm Clip-Filter Nikon Z XL
The Astronomik H-alpha filter is ideal for imaging HII regions from both light-polluted and dark observation sites. The Astronomik H-alpha filter significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background, allowing for long exposure times for deep and high-contrast images. The filter blocks the emission lines of high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, the maxima of typical LED lights, most lines of natural airglow, as well as most of the distracting moonlight. The Astronomik H-alpha filter effectively blocks all unwanted light from wavelengths other than 656nm, from ultraviolet (UV) to infrared (IR). The Astronomik H-alpha filter MUST NOT BE USED for solar observation! Difference between Astronomik 12nm, 6nm and 4nm filters The choice between 12nm, 6nm and 4nm Full-Width-Half-Maximum (FWHM) filters depends on your imaging conditions and camera type. There is no universal “best” option - each FWHM serves a specific purpose. The 6nm Astronomik Narrowband-Emissionline filters are usually the best choice for astrophotography. They are ideal for imaging faint objects in star-crowded regions of the milky way, as they typically halve the number of stars in the image compared to 12nm filters, greatly simplifying image processing. The 6nm Narrowband-Emissionline filters are the first choice, especially if you are using a CMOS astro camera or a modern system camera with very low dark current, or if you are observing from a location with strong light pollution. The excellent suppression of the sky background allows you to use long exposure times. The 6nm filters provide a dark background and outstanding details of faint nebulae. The Astronomik MFR coating Both the Astronomik MFR and MaxFR coatings offer extremely high contrast, minimized stray light, no halos and needle-sharp stars. In addition, they provide the best possible blocking across the entire spectral range from UV to IR. 6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/15 without visible performance loss. Clip-Filter for mirrorless Nikon Z full-frame cameras Mirrorless full-frame Z-series cameras from Nikon are an excellent choice for astrophotography. With Astronomik Clip-Filters, you can use our full range of filters with your camera to capture stunning images. Whether paired with a camera lens or a telescope, our Clip-Filters ensure maximum image quality and performance from your setup. The Astronomik Clip-Filters offer a number of practical advantages that make them an ideal choice for astrophotographers: Installing and removing the Astronomik Clip-Filter is very quick and easy and requires no extra tools or modifications to the camera body. They can be changed at any time, even at night. All lens functions, such as focus, aperture, and image stabilization remain fully functional. The Astronomik Clip-Filters are held securely in place without stressing the high-quality glass. The Astronomik Clip-Filters are designed and optimized for use with both standard camera lenses and telescopes. Through the Astronomik Clip-Filters, we were able to solve several common issues faced by astrophotographers: Large filters for large camera lenses are very expensive. Using a filter holder between the camera body and the lens prevents focusing to infinity. For very fast telescopes (low f-number) like the Vixen R200SS or the Takahashi “Epsilon” astrograph, a filter drawer or filter wheel can not be used because the distance to the corrector lenses would be changed. Long exposure times lead to dust settling on the camera’s sensor chip. Additionally, all Astronomik Nikon Z XL Clip-Filters serve as an excellent dust shield, protecting the sensor during long exposures. If you only need a dust shield without filtering effects, the Astronomik MC-Clear Nikon Z XL Clip-Filter is the right choice. Use Astronomik filters for your Nikon Z full-frame camera and enjoy marvelous images with an ultra light equipment! Compatible Nikon Z full-frame cameras Model Compatibility Nikon Z 5 Nikon Z6 Nikon Z 6II Nikon Z6III Nikon Z7 Nikon Z 7II Nikon Z 8 Nikon Z 9 Nikon Z f Nikon APS-C cameras Non-compatible lenses Model Compatibility Original Nikon Z teleconverter TC-2.0x Technical Data Guaranteed transmission of more than 90% at the H-alpha line (656nm) Typical transmission of 93% at the H-alpha line Full-Width-Half Maximum (FWHM): 6nm Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters) Finely polished optical glass, free of any striae, residual stresses, and bubbles Extremely scratch-resistant and durable coating Completely resistant against high humidity and aging effects Astronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters) Parfocal with other Astronomik filters Diffraction-limited Optimized spectral windows Delivered in a high-quality, long-lasting filter box Made in Germany Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Thanks to the high-precision machining of the glas substrate, all Astronomik filters are parfocal. The wedge errors are far below all common tolerances. Therefore, all issues concerning focal distances and the exact alignment of images from each color channel are effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR and MaxFR coatings are designed for optimal performance across a wide range of focal ratios of the optics used. Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios for best performance of that specific filter.

Astronomik SII 6nm 31mm
The Astronomik SII filter is ideal for imaging nebulae showing sulfur emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 671.7nm and 673nm (SII lines) and the sky background. The Astronomik SII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 671.7nm and 673nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik SII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at both SII lines Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik OIII 6nm 50mm
The Astronomik OIII filter is ideal for imaging nebulae showing oxygen emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 496nm and 501nm (OIII lines) and the sky background. The Astronomik OIII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 496nm and 501nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik OIII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm) and 88% (6nm and 4nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm and 4nm) at the major OIII line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik OIII 6nm 50 x 50mm², unmounted
The Astronomik OIII filter is ideal for imaging nebulae showing oxygen emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 496nm and 501nm (OIII lines) and the sky background. The Astronomik OIII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 496nm and 501nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik OIII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm) and 88% (6nm and 4nm) at the major OIII line (501nm)Typical transmission of 95% (12nm) and 92% (6nm and 4nm) at the major OIII line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik SII 6nm 50mm
The Astronomik SII filter is ideal for imaging nebulae showing sulfur emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 671.7nm and 673nm (SII lines) and the sky background. The Astronomik SII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 671.7nm and 673nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik SII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at both SII lines Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik SII 6nm 50 x 50mm², unmounted
The Astronomik SII filter is ideal for imaging nebulae showing sulfur emissions from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 671.7nm and 673nm (SII lines) and the sky background. The Astronomik SII filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 671.7nm and 673nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik SII 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars.12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at both SII lines (671.7nm and 673.0nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at both SII lines Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik H-alpha 6nm 50mm
The Astronomik H-alpha filter is ideal for imaging hydrogen nebulae from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background. The Astronomik H-alpha filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 656nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik H-alpha 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at the H-alpha line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik H-alpha 6nm 50 x 50mm², unmounted
The Astronomik H-alpha filter is ideal for imaging hydrogen nebulae from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background. The Astronomik H-alpha filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 656nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik H-alpha 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at the H-alpha line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik H-alpha 6nm 1,25" (M28,5)
The Astronomik H-alpha filter is ideal for imaging hydrogen nebulae from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background. The Astronomik H-alpha filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 656nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik H-alpha 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at the H-alpha line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.

Astronomik H-alpha 6nm M49
The Astronomik H-alpha filter is ideal for imaging hydrogen nebulae from both light-polluted and dark observation sites. It significantly enhances the contrast between objects emitting light at 656nm (H-alpha line) and the sky background. The Astronomik H-alpha filter completely filters out the emission lines from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, as well as all lines of natural airglow and most of the distracting moonlight.With a narrow bandwidth of either 12nm, 6nm or 4nm and high transmission rates, the filter effectively blocks all unwanted light from wavelengths other than 656nm from ultraviolet (UV) to infrared (IR).In areas with little light pollution, the background signal in images is usually limited by the sensor's dark current rather than light pollution. Therefore, further suppression of the sky background by reduction of the Full-Width-Half Maximum (FWHM) does not bring out more details in the object. The Astronomik H-alpha filter MUST NOT BE USED for solar observation!Imaging with Astronomik Narrowband-Emissionline filtersImaging with Astronomik Narrowband-Emissionline filters is the best way to capture great images from light-polluted sites as they effectively block all kinds of light pollution. An Astronomik H-alpha filter is usually the first step in this field of astrophotography, allowing you to take deep and contrasty images even under heavy light pollution or a full moon. Astronomik H-alpha filters are ideal for imaging all red-glowing nebulae. Astronomik OIII filters expand your imaging possibilities by capturing greenish and blueish structures, making planetary nebulae, star-forming regions and supernova remnants great targets. Completing your filter set with an Astronomik SII filter enables you to create false-color emission line images similar to those produced by the Hubble Space Telescope using the HSO (H-alpha, SII, OIII) palette. Difference between Astronomik H-alpha 4nm, 6nm and 12nm filters The 4nm and 6nm Astronomik Narrowband-Emissionline filters are ideal for imaging faint objects in star-crowded regions of the milky way. They are also recommended if you use a camera with very low dark current or if you are observing from a location with extreme light pollution.The 12nm Astronomik Narrowband-Emissionline filters are developed for use with typical DSLR cameras with CMOS sensors and CCD cameras with normal or high dark current. They are also the preferred choice for cameras with an integrated or dual guiding sensor, as they provide more guiding stars.Difference between Astronomik MFR and MaxFR coatingBoth the Astronomik MFR and MaxFR coatings give you the best possible blocking across the entire spectral range from UV to IR, extremely high contrast, minimized stray light, no halos and needle-sharp stars. 12nm MFR-coated filters can be used in all instruments with aperture ratios from f/3 to f/∞ without significant performance loss.6nm MFR-coated filters can be used in all instruments with aperture ratios from f/4 to f/∞ without significant performance loss.4nm MFR-coated filters can be used in all instruments with aperture ratios from f/4.5 to f/15 without significant performance loss.The MaxFR coating is designed to work perfectly with fast optical systems. For 12nm filters with MaxFR coating, this means unlimited usability from f/1.7 to f/6 and approximately 85% of the maximum transmission at a f/1.4.For 6nm filters with MaxFR coating, this means unlimited usability from f/2.2 to f/6 and approximately 90% of the maximum transmission at a f/2.4nm filters with MaxFR coating are currently in development.Filters for even faster optics are available on request.Technical dataGuaranteed transmission of more than 90% (12nm, 6nm and 4nm) at the H-alpha line (656nm)Typical transmission of 96% (12nm) and 93% (6nm and 4nm) at the H-alpha line Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)Finely polished optical glass, free of any striae, residual stresses, and bubblesExtremely scratch-resistant and durable coatingCompletely resistant against high humidity and aging effectsAstronomik MFR coating (Astronomik Deep-Sky RGB, UV-IR Block L-1, L-2, L-3, and Narrowband-Emissionline filters)Parfocal with other Astronomik filtersDiffraction-limitedOptimized spectral windowsDelivered in a high-quality, long-lasting filter boxDue to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore effectively eliminated. All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR coating is designed for optimal performance across a wide range of focal ratios of the optics used.Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline filter box, you will find a label detailing the precise spectral data for that specific filter, including the maximum transmission and the recommended range of focal ratios.




