Optolong LRGB CCD Filter Set - 1.25" Mounted for Astrophotography - Enhance Deep Sky Imaging for Telescopes & Cameras

The LRGB Filter Set from Optolong features a full array of four 1.25" mounted filters. The filter set comes with Red, Green, Blue, and Luminance filters. Designed for de-bayered monochrome CCD and CMOS cameras, these filters are excellent for both planetary and deep-sky imaging. Like all Optolong filters that are designated “CCD”, this filter set blocks infrared wavelengths from 700nm to 1100nm so there is no need to use a separate IR-Cut filter.

The transmission of each filter is designed for maximum contrast and beautiful results. There is a gap between the green and red filters that improves color balance and separation by blocking out the Sodium line at 589nm. Also, OIII emission is allowed to overlap on the blue and green filters for more natural color.

The Optolong 1.25” LRGB Filter Set is made with Schott glass that has been multi-coated with an ion-assisted deposition technology to ensure scratch resistance and stability on the central wavelength, or CWL. Each filter cell is made of lightweight, strong metal and is CNC machined, sand-blasted, black anodized, and then laser engraved. The result is a super thin filter cell that will produce a clear aperture of 26mm.

Quality Filter Materials:

• Schott B260 substrate material from Germany, 3.0mm thick

• Multiple layers of anti-reflection non-cementing coatings applied via electron-beam gun evaporation with Ion-assisted deposition

Optolong Filter Manufacturing Processes and Parameters

• Filter substrate is fine-optically polished to 1/4 wave and <30 parallelism over both surfaces

• Surface quality, according to MIL-O-13830, is 60/40

• 95% transmission at bandpass

• Infrared wavelength 700-1100nm cut-off

• Optolong’s planetary rotation system is a homogenous and precise coating procedure that ensures both high transmission of pass-band and optical density of off-band

• Each filter comes with a plastic case with high-pressure EVA case lining

• Thin metal cells have a clear aperture of 26mm for 1.25” filters

About Optolong

Optolong is the Astronomy Filters division of Yulong Optics, an optical filter design, and processing company out of Kunming, China that has provided filters for over 700 optical companies since 1999. All Optolong filters pass European Union RoHS requirements and have been certified by TUV Rheinland and Bureau Veritas.