The CLS Light Pollution Filter - 2-Inch Round Unmounted by Astronomik:
The Astronomik CLS is an excellent filter for black and white and color imaging of nebulae, galaxies and star clusters with astronomical instruments of any size. By blocking the spectral lines of mercury and sodium-vapor lamps, and letting the largest part of the visible light and H-alpha emissions pass, the CLS filter will effectively block out most surrounding light pollution, eliminating that annoying orange glare.
The filters are optimized for use with filter to aperture ratios of 1:3 to 1:15. By remaining within these aperture ratios, aberration and comma are eliminated.
Astronomik CLS Light Pollution Filter - Transmission Information:
- 92-percent transmission at 486nm (H-beta)
- 92-percent transmission at 496nm (OIII)
- 92-percent transmission at 501nm (OIII)
- 97-percent transmission at 656nm (H alpha)
- Pass from 450 to 540nm and beyond 650nm
- Parfocal with other Astronomik filters
- Glass thickness: 1mm
- Highly resistant against high humidity, scratches and aging effects
- Diffraction limited, the filter will not reduce the optical performance of your telescope!
- Astronomik filters are delivered in a high-quality, long lasting, filter box
OPT Product Number: AK-CLS-2