City Light Suppression Light Pollution Broadband Filter Features: 1. Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and optical density of off-band. 2. The CLS broadband filter is designed to improve the visibility of various deepsky objects. By selectively reducing the transmission of wavelengths of light pollutants. Specifically those produced by artificial lightings including mercury vapor lamps, both high & low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow). 3. Ultra-thin filter cell minimize vignetting by maximize possible. 4. 90% transmission of main nebula emission lines (i.e. Ha 656nm, OIII 496nm&500nm, SII672nm and H-beta 486nm). 5. 0.1% transmission of off-band, specifically the major emission lines of artificial light pollution (i.e. Na 589nm, Hg 435nmand 578nm). 6. Suitable for color CCD cameras and unmodified DSLRs. Notes: The CLS EOS -C is compatible with the Camera type: 7D Mark II, 80D/800D , 77D/70D/760D/750D/700D 650D/600D, 550D/500D, 400D, 100D/1100D/1200D/1300D, this Filter is not for EF-S camera Lens. UHC filter can be used not only for celestial observations but also for astrophotography compatible with 7D MkII, 7D, 20D, 20Da, 30D, 40D, 50D, 60D + 60Da, 70D, 80D, 300D / Digital Rebel / Kiss Digital, 350D / Digital Rebel XT / Kiss Digital N, 400D / Digital Rebel XTi / Kiss Digital X, 450D / Rebel XSi / Kiss X2, 500D / Rebel T1i / Kiss X3, 550D / Rebel T2i / Kiss X4, 600D / Rebel T3i / Kiss X5, 650D / Rebel T4i / Kiss X6, 700D / Rebel T5i / Kiss X7, 750D / Rebel T6i / Kiss X8, 760D / Rebel T7i / Kiss X9, 1000D / Rebel XS / Kiss F, 1100D / Rebel T3 / Kiss X50，1200D , 1300D , 100D. This filter is not for EF-S camera lens.