On Sale Optolong CLS Filter - EOS Full Frame
- Broadband filter designed for deep sky viewing and astrophotography
- Ideal for sub-rural locations with moderate light pollution
- Reduces unwanted skyglow and light pollution from artificial light sources, particularly mercury vapour lamps.
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- Blocks artificial light from mercury vaopour lamps, both high and low pressure sodium vapour lights and the unwated natural light caused by neutral oxygen emission in our atmosphere
- Maximum transmission of the main nebula emission lines: OIII, H-beta, NII, H-alpha as well as SII
- Can be used for visual observations as well as astrophotography
- Ideal for sub-rural areas with moderate light pollution
- Ultra-thin filter cell to maximise the compatibility with most filter wheels
- Multi-layers anti-reflection coatin
For astronomy cameras, it needs to be used in combination with an IR/UV cut filter. Alternatively the CLS-CCD filter can be used as it cuts off the infared and ultraviolet wavelengths. In DSLR the IR/UV filter is embedded in teh camera so the standard CLS filter is sufficient.
Light pollution filters do not eliminate the effects of light pollution or increase the object's brightness. It does increase the contrast between nebulae and night sky.
| Passing Band | Broadband |
| Glass Thickness | 2.0mm (1.25" & 2" filters); 1mm (clip series) |
| Optical Flatness | 1/4 (wavefront) |
| Band-pass transmission | 90% across major nebulae bandpass |
| Coating | Fully multi-coated |
| Surface quality | 60/40 (in accordance with US military watch MIL-O-13830 |
| Parallelism | 30" |
| Glass type | Schott Monolithic Optical Substrate |
| Available sizes | 1.25", 2", clip on EOS-C, Clip on EOS Full Frame |
About Optolong
Optolong Optics is a specialist manufacturer of astronomy and astrophotography filters that are adored by astrophotographers worldwide since it was established in 1999. Particularly famous for their bandpass narrowband filters, “L-Pro” , "L-eXtreme" and "L-eNhance” which enables high quality imaging from simple one shot colour cameras, it’s hard to find a serious astrophotographer that has not longed for an Optolong filter in their tool kit.
Product Code: OPT-11804