Use the Alpine Astronomical Baader L-RGB-C CCD Imaging Filter Set during monochromatic imaging for creating stunning custom composite images of nebulae, planets, and other celestial objects. By capturing a single subject in each of the three primary colors—red, green, and blue—and stacking them in post production using specialized software, you can create any colors you want or highlight your subject's natural properties.
In addition to the three primary imaging filters, this set also includes a clear focusing filter and a luminance filter. The clear filter is used first to sharply focus the view before imaging with the colored filters, as it makes it much easier for the eye to accurately judge the focus sharpness. And since the clear filter is parfocal with the colored ones, once the focus is set with the clear you can be sure the images captured with the colored filters will be sharp as well.
The luminance filter blocks ultraviolet (UV) and infrared (IR) light to allow only the visual spectrum between to pass through. Since many of today's imaging sensors are sensitive to IR and UV wavelengths, you can stack the luminance with any of the other three colored filters to eliminate ghosting caused by bands outside the visible spectrum "bleeding" into your image—especially with the blue and red.
Each filter is planeoptically polished and anti-reflection multi-coated to ensure high and uniform light transmission across the entire surface to maximize brightness and limit distortion, halos, and reflections. With a greater than 95% transmittance, and all filters being parfocal, exposure times remain unchanged when you switch colors or if you don't use them at all. These filters are offered here as an unmounted 50.4mm round option for custom applications and imaging systems.
- Maximized color contrast for each of the three color filters, made possible by the steep slopes at their transmission curves combined with placement of the spectral wavelength window
- Oxygen-III emission line double-weighted in the blue and green channel, with maximum peak transmission for improved deep sky signal-to-noise ratio yield
- Red filter provides maximum transmission of H-alpha and sodium-II emission lines, while also completely blocking near-IR and IR wavelengths from 680nm to 1200nm
- Light-pollution blocking of street lamps—especially mercury and sodium-vapor lamps—at 580nm with the green and red filters blackens the sky background and maximizes color balance and separation
- Not for solar viewing or imaging. Serious permanent injury may occur, up to and including blindness