Optolong CLS-CCD Clip Filter Canon EOS APS-C

The Optolong CLS-CCD Clip Filter Canon EOS APS-C (City Light Suppression) is designed to make deep-sky objects visible under light-polluted skies. In addition to typical light pollution sources (sodium and mercury vapor lamps, skyglow), this variant also blocks infrared waves from 700-1100 nm. This makes this filter ideal for modified DSLRs and CCD color cameras, where IR light often lands unwanted on the sensor and leads to blur.

The CLS-CCD allows the primary emission lines of nebulae - OIII (496/500 nm), H-beta (486 nm), NII (654/658 nm), H-alpha (656 nm) and SII (672 nm) - to pass through without loss. This increases contrast and makes fainter details visible, such as the outer edges of emission and planetary nebulae. Supernova remnants also benefit from the additional IR filtering.

Thus, compared to the standard CLS filter, the CLS-CCD provides an even cleaner signal and better color neutrality in astrophotography with modified cameras. For those shooting under urban or suburban skies, this provides a noticeable improvement in image quality and contrast.

Application
The Optolong CLS-CCD Clip Filter Canon EOS APS-C is ideal for:

• Deep-sky photography with modified Canon EOS APS-C DSLRs
• Use with CCD color cameras sensitive to IR light
• Photography of emission nebulae, planetary nebulae and supernova remnants
• Improving contrast and visibility of fainter details at the edges of nebulae

Specifications

• Suitable for: Canon EOS APS-C (modified DSLRs) and CCD cameras
• Material: shot glass
• Mount: clip-in (1.25″ equivalent size)
• Type: broadband filter (CLS-CCD)
• Optics coating: multi-coated
• Transmission: approx. 80%
• Surface accuracy: λ/4
• Application: photographic and visual

Note
This filter should never be used as the sole sunscreen.