About the Lumicon Ultra High Contrast (UHC) Filter - 1.25"...
The original Lumicon Ultra-High-Contrast Narrow Bandpass Filter (24nm) isolates just the two doubly-ionized oxygen lines (496 and 501nm lines) and H-beta line (486nm) emitted by planetary and most emission nebulae, while blocking, completely the rest of the overall spectrum of light. The result is extreme contrast between the black background of space and the delicate photons of nebula light needed for near-photographic views of the Orion, Lagoon, Swan and planetary nebulae, among others. This makes the Lumicon UHC Filter the best all-around dark-sky filter on the market today.
See for yourself - it'''s truly amazing what the Lumicon UHC Filter allows you to see! Lumicon tests every filter individually on a Perkin-Elmer Double Beam spectrophotometer, inscribing on the filter its percentage of transmission for each of the primary lines. Do not settle for cheap, foreign-made imitations.
Not intended for photographic use.
Lumicon Ultra High Contrast (UHC) Filter - 1.25" Features...
- Isolates just the two doubly-ionized oxygen lines (496 and 501nm lines) and H-beta line (486nm) emitted by planetary and most emission nebulae, while blocking, completely the rest of the overall spectrum of light
- Provides extreme contrast between the black background of space and the delicate photons of nebula light needed for near-photographic views
- Tested individually on a Perkin-Elmer Double Beam spectrophotometer, inscribing on the filter its percentage of transmission for each of the primary lines
- Consists of two elements, sandwiched coatings, and anti-reflection coatings on all surfaces to
prevent ghosting
Lumicon Ultra High Contrast (UHC) Filter - 1.25" Specifications...
Filter Type: Ultra High Constrast
Filter Size: 1.25"
Presentation: Round, threaded cell
Bandpass: 22-26nm
Optimum Exit Pupil (Light Polluted Skies): 1-4mm
Optimum Exit Pupil (Dark Skies): 2-6mm
Lumicon Product Number: LF3025