Telescope Filter 2" CLS Broadband Filter, Reduce City Light Pollution Suitable for Deep Sky Visual Astronomical Photography

SVBONY city light suppression broadband filter is designed to improve the visibility of various deep sky objects,
By selectively reducing the transmission of wavelengths of light pollutants;specifically those produced
by artificial lighting including mercury vapor lamps;both high and low pressure sodium 

vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere;such as sky glow 

Using:
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 getting more details for both visual and photographic purpose at sub-rural area

Outstanding Features:

Coating:
Multi layers anti-reflection coating.Non cementing optical substrate coating

Filter:
Ultra-thin filter cell minimize vignetting by maximize possible

Extinction Treatment:
Aerometal material precise CNC machining sand blasting Process black anodized finish extinction treatment to prevent reflection laser 

CLS:
engraving no fading CLS with wider pass-band than UHC and hence is more favored when observing under mild to moderate light pollution

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

Warning:
the filters of SVBONY are not designed for sun observation;don not look directly into the sun with SVBONY filter;otherwise it will burn the eyes

Specifications:
Type: city light suppression filter (CLS Filter) Material: optical glass lens;aluminum frame Thread: Standard M48.5x0.75mm

Package includes:
1xSVBONY 2" CLS filter
1xsturdy plastic case