The Astronomik OWB (Original White Balance) Type 3 filter is not a traditional astronomical filter. Instead, it is designed to enable modified DSLR, CCD and CMOS cameras, which have had their inbuilt color correction or infrared (IR) filter removed or replaced, to be used for regular photography. This filter allows a modified DSLR to be used for both astrophotography and everyday photography, eliminating the need to dedicate a camera solely to astronomical tasks.DSLR cameras are modified for astronomical use by removing or substituting the inbuilt color correction filter with one that has a greater transmission of H-alpha light. When doing this, they lose their white balance capability for regular photography. The Astronomik OWB Type 3 filter restores the spectral sensitivity of the modified DSLR to its original range, making the camera functional for everyday photography again. Essentially, the Astronomik OWB Type 3 filter mimics the conventional built-in filter of the camera.The Astronomik OWB Type 3 filter allows the modified camera to work with its pre-set white balance settings, including the automatic white balance (AWB), which is not possible with modified DSLRs without this filter. Suitability of the Astronomik OWB Type 3 filtersDSLR photography (astro-modified): Very good, restores standard white balance for regular photographyDSLR photography (Full Spectrum modified): Very good, restores standard white balance for regular photography Technical data 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.