Optolong CLS-CCD broadband filter
1. Optolong CLS-CCD Introduction
The CLS-CCD 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). 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 photographic purpose at light pollution area.
CLS-CCD is different from CLS with infrared wavelength 700-1100nm cut-off.
Fit with color CCD cameras and modified DSLRs for astrophotography.
Work well on most emission nebulae, planetary nebulae and supernova remnants.
Noticeable boost in contrast and visibility of the fainter outer detail.
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 Optolong are not designed for sun observation. DO NOT LOOK AT THE SUN WITH OPTOLONG FILTER. You would be BLIND if you fail to observe the warning.
2. Optolong CLS-CCD Spectrum and Characteristic
Substrate: Optical glass
Blocking range: 300-1100nm
Blocking depth: light pollution line blocking >99%
Surface quality: 60/40
Transmitted Wavefront RMS: λ/4
How to read the chart?
▲The horizontal axis is the Wavelength in Nanometers(nm).
▲The vertical axis is transmission in %.
▲The RED line shows the transmission of the CLS-CCD filter. Green line shows the emission of nebula. The artificial emission lines are shown in ORANGE.
Outer Box: silve box
Plastic Box: PP material
Lining: imported high pressure white EVA material