SVBONY Telescope Filter 2 inches CLS Filter City Light Pollution Reduction Filter Broadband Filter Suitable for Deep Sky Visual Astronomical Photography 2inch
SVBONY Telescope Filter 2 inches CLS Filter City Light Pollution Reduction Filter Broadband Filter Suitable for Deep Sky Visual Astronomical Photography
Product Features
- Evaporation with Ion-assisted deposition coating technology for durability and resistance to scratching;as well as stability on CWL (central wavelength) no deviation affected by temperature change
- Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass band and Optical density of off-band
- 90% transmission of main nebula emission lines;such as Ha 656nm;OIII 496nm;500nm;SII672nm and H-beta 486nm
- 0.1% transmission of off-band;specifically the major emission lines of artificial light pollution;such as Na 589nm;Hg 435nmand 578nm
- Suitable for color CCD cameras and unmodified DSLR Urban optical filter can effectively suppress urban harmful light and improve the contrast of shooting target