The ZWO LRGB2 Filter Set includes four 2” mounted astrophotography filters that pass red, green, and blue bands of light as well the full luminance spectrum across the visible band. By taking individual images with each of these filters and a monochrome astronomy camera and combining the separate images with standard processing techniques, you can create beautiful correct-color images of planets and deep-sky objects.
This premium filter set is designed to approximately equalize the sensor response of the ASI1600 monochrome camera, and the RGB color combination is weighted to approximately 1:1:1 for accurate color rendering. These filters also work well with other monochrome astronomy cameras.
All filters have a mechanical thickness of 5mm, with another 2.5mm added for the thread. Each filter is more parfocal with a thickness of 1.9+/-0.03mm. The filters are mounted in cells with standard M48x0.75 threads for use in most filter wheels that accommodate 2” filters.
The precision passbands of the LRGB filters include a gap between red and green to improve color balance and partially block the sodium line at 589nm to suppress light pollution from low and high pressure sodium lamps. The blue and green filter passbands overlap slightly to include emission from OIII to help achieve a more natural color when imaging nebulae. The ZWO LRGB filters also block infrared wavelengths from 700nm to 1100nm which means a separate IR-cut filter is not required. Each filter has a transmittance of at least 92% in band, and each is optically polished to ¼ wave to help you get superior images. All surfaces have multi-layer antireflection coatings for increased transmittance and elimination of ghost reflections.
This set is not suitable for imaging with DSLRs or one-shot color astronomy cameras because they include a Bayer array to achieve color images intrinsically.