SVBONY 2" CLS Light Pollution Broadband Filter Suitable for Visual & Astronomical Photography

Description:
The SVBONY CLS broadband filter is designed to improve the visibility of various Deepsky objects. By selectively reducing the transmission of wavelengths of light pollutIion, specifically those produced by lightings including mercury lamps, both high low sodium lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow). Together with the highly transparent in main nebula emission lines at OIII(496nm and 500nm), H-beta (486nm), NII(654nm and 658nm), H-alpha(656nm) as well as SII(672nm), the filter is suitable for enhancing the contrast and details for both visual and photographic purpose at sub-rural area.
Features:
1. Multi-layers anti-reflection coating2. Non-cementing optical substrate coating3. Electron-beam 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.4. Planetary rotation system offers precision and homogeneity of coatings ensuring good value on transmission of pass-band and Optical density of off-band.5. Ultra-thin filter cell minimize vignetting by maximize possible6. Aerometal Material Precise Machining Sand Blasting7. Process Black Anodized Finish Extinction Treatment to8. Prevent Reflection Laser No Fading9. 90% transmission of main nebula emission lines (i.e. Ha 656nm, OIII 496nm500nm, SII672nm and H-beta 486nm).10. 0.1% transmission of off-band, specifically the major emission lines of light pollution (i.e. Na 589nm, Hg 435nmand 578nm).11. Suitable for CCD cameras and unmodified DSLRs12. CLS with wider pass-band than UHC and hence is more favored when observing under mild to moderate light pollution.13. Light pollution filter do not eliminate the effects of light pollution or increase the object’s brightness. In many cases, they increase the contrast between nebula and night sky, not brightening the nebula.14.WARNING: The filters of SVBONY are not designed for sun observation. DO NOT LOOK AT THE SUN WITH SVBONY FILTER. You would be BLIND if you fail to observe the warning.
Specifications:
1.Brand: SVBONY2.Type: CLS Filter3.Material: Optical glass lens, Aluminum Frame4.Shape: Round5.Thread: Standard M48*0.75mm6.Net Weight: 5.2g / 0.18oz
Package includes:
1 x SVBONY 2 inch CLS Filter1 x Sturdy Plastic Case



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