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Lumicon Oxygen III (OIII) Filter - SCT Rear Cell - LF3050

Lumicon Oxygen III (OIII) Filter - SCT Rear Cell - LF3050 - Main image
$238.98 $322.95 In stock

Category: Telescope Accessories

The renowned, original Lumicon OIII narrow bandpass filter (11nm) for the Cassegrain Rear Cell isolates just the two doubly-ionized oxygen lines (496 and 501nm lines) emitted by planetary and emission nebulae while blocking the rest of the overall spectrum of light. The result is extreme contrast between the black background of space and the delicate photons of OIII light needed for near-photographic views of the Veil, Ring, Dumbbell and Orion nebulae, among other objects. See for yourself; it's truly amazing what the OIII filter allows you to see! Lumicon tests every filter individually on a Perkin-Elmer Double-Beam spectrophotometer, inscribing on the filter its % transmission for each of the primary lines. Do not settle for cheap imitations.


Not intended for photography (use the Lumicon Deep Sky Filter).

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Customer Reviews (4.8 / 5 · 5 reviews)

Olivia ★★★★★

Was a bit worried about the fit on my SCT, but the rear cell design threaded on perfectly and snug. First clear night out, the Veil Nebula looked like actual twisted smoke instead of a faint smudge. Definitely worth the upgrade for anyone hunting planetary nebulae.

Joseph C. ★★★★★

Last night Jupiter popped into view and the OIII made the bands look like etched glass against the sky. The 11nm bandpass really isolates the detail without washing out the background.

Joseph J. ★★★★★

Finally had a clear night to test this, and the Veil Nebula popped with incredible contrast—the 11nm bandwidth really cuts through light pollution. Screwed right onto my SCT rear cell without any adapters needed.