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Lumicon 1.25" Oxygen III (OIII) Filter - LF3040

Lumicon 1.25" Oxygen III (OIII) Filter - LF3040 - Main image
$111.75 $161.95 In stock

Category: Telescope Accessories

The renowned, original Lumicon 1.25" OIII narrow bandpass filter (11nm) 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 (5.0 / 5 · 5 reviews)

Owen U. ★★★★★

Clearer views of the Veil Nebula than I’ve managed with any other filter I’ve tried, those two oxygen lines really punch through the background sky. The 11nm bandpass lets just enough through to keep stars point-like, and it threaded into my 1.25" eyepiece without any fuss.

Henry V. ★★★★★

Finally got to test this on the Dumbbell Nebula and the contrast against the background sky was incredible. The 11nm bandwidth really makes the faint structure pop without washing out the stars around it. My only regret is not buying it sooner.

Brian U. ★★★★★

Took it out to the Veil Nebula on a moonlit night, and the 11nm bandpass made the faint filaments pop like I’d never seen them before. The threads are solidly machined and it threaded onto my eyepiece without any wobble. Exactly the boost I needed for these dim targets.