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Baader OIII 31 mm f/2 Highspeed CMOS Optimized 6.5nm Filter

SKU: BAD-FCOIIIHS-RD31
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Baader OIII 31 mm f2 Highspeed CMOS Optimized 6.5nm Filter OIII 31mm Highspeed Filter
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$208.00

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Baader OIII 31 mm f/2 Highspeed CMOS Optimized 6.5nm Filter

With 6.5 nm FWHM, this filter from Baader Planetarium is recommended for extremely fast optical systems from f/3.4 to f/1.8, like the Celestron RASA astrographs. The filters are designed to allow for 1:1:1 exposures. This matches the typical CMOS quantum efficiency and s/n ratio. The filters are optimized for CMOS cameras and will also work well with CCD cameras. Baader has designed this 31 mm Oxygen III (OIII) filter to be precision-grade and provide astrophotographers an excellent complement to their imaging setup.

This Baader OIII f/2 highspeed filter is CMOS optimized with Life-Coat. This coating is a hard coating that will not peel, flake, and will not physically degrade even in the most extreme weather conditions. This coating is also designed to withstand repeated cleaning with fine optical cleaning equipment. This coating is so durable that Baader is confident it will last the life of the filter.

Not only do the filters have sealed coating edges with the Life-Coat, but they are also hard coated with Reflex-Blocker and planoptically polished. All of the edges are blackened for increased contrast and eliminate any reflection that would come from light falling on the edge of the filter. The filters are also equipped with a filter-lead-side-indicator in the form of a frontside outer rim.

About OIII Filters

OIII narrowband filters isolate just the two doubly-ionized oxygen lines emitted by planetary and emission nebulae and block the rest of the overall spectrum of light. This results in extreme contrast between the black sky background and the faint photons of OIII light needed for detailed views of the Veil, Ring, Dumbbell, Crescent and Orion nebulae, and other objects.

Baader Highspeed 31 mm CMOS Optimized Filter Features

  • Transmission Ranges: OIII
  • Filter Thickness (w/out glass) 2 mm
  • Half Bandwidth: 6.5 nm
  • Central Wavelenth: 500.7 nm
  • AR-Coating: Reflex Blocker hard coated and planoptically polished
  • Filter Size: 31 mm
  • Threaded: No, Drop-In
  • Usage: CMOS, CCD, OIII
  • Mounted: Yes
  • Filter Type: Narrowband
  • FIlter Shape: Round
  • Feature Highlight: CMOS-Optimized with Life-Coat