Optolong Moon SkyGlow Filter - 2" Mounted - MSG-200

Optolong Moon and Skyglow Filter - 2”

This Moon & Skyglow Filter by Optolong is ideal for visual observations as well as astrophotography. You will see a darker background sky because of the blocking of natural skyglow at 589nm and light emissions causing artificial light pollution. Therefore, contrast increases between the sky and the celestial object, revealing more details. Great for nebulae, galaxies, globular star clusters, planetary nebulae and even the moon.

The Optolong 2” Moon & Skyglow Filter 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 45mm.

Quality Filter Materials:

• Schott B260 substrate material from Germany, 2.0mm thick

• CNC machined and black anodized aero-metal filter cell that is ultra-thin to provide largest clear aperture; Laser-engraved to prevent fading

• 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

• 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

• Thin metal cells have a clear aperture of 45mm for 2” filters

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

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.