Optolong UBVRI Filter Set - 1.25" Mounted Astronomy Filters for Telescope Photography - Perfect for Deep Sky Imaging & Astrophotography

This versatile UBVRI filter set from Optolong features five 1.25" round filters that have been mounted for your convenience. These filters are ultraviolet (U), blue (B), visual (V), red (R), and infrared (I).

The Optolong 1.25" UBVRI Filter Set is produced using multi-coated Schott glass with an ion-assisted deposition technology to maintain stability and scratch resistance on the central wavelength (CWL). This filter set is designed to be used in color filter wheels that accept 1.25" mounted filters in a round format.

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
• 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

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. 

 Image shows an unmounted set of filters. You will receive a mounted UBVRI set.