Tele Vue 17mm Nagler Type 4 Eyepiece - 2" - EN4-170
The Lumicon Deep-Sky Thread on Filter for Schmidt-Cassegrain Rear Cell is the foremost broadband filter, efficiently blocking all mercury-vapor and high & low-pressure sodium-vapor lamp light, neon lights and airglow while allowing the rest of the visible spectrum through. The superior contrast gain between the object you're viewing and the black background of space allows you to view galaxies, nebula, star clusters, comets, etc. wonderfully when observing from light-polluted urban skies, making it the best all-around visual light pollution filter. The Cassegrain Deep Sky Filter threads onto your telescope's SCT rear-cell, and presents male SCT threads for accessory attachment. The Cassegrain filter cell allows you to change eyepieces without threading/unthreading the filter.
The Lumicon Deep-Sky Filter's high transmission in the H-alpha end of the spectrum makes it the only premium astrophotographic filter on the market for not only color photographs, but also for black & white photos and CCD work. Lumicon tests every filter individually on a Perkin-Elmer Double-Beam spectrophotometer, inscribing on the filter its % transmission for each of the primary spectral lines. Do not settle for cheap, foreign-made, low-transmission broadband filters.
- Intended for viewing nebulae from light-polluted skies
- Blocks all mercury vapor and high & low-pressure sodium vapor lamp light, neon lights, and airglow, while transmitting the rest of the visible spectrum
- The best all-around visual light pollution filter for use in urban skies
- This filter also provides high-contrast views of the Martian polar caps
Dimensions & Specifications
Schmidt-Cassegrain Rear Cell
SCT Rear Cell
Deep Sky Filters
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