We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Black 1.25-inch Oxygen III narrowband filter with ultra-hard coating

Celestron

Celestron 93623 1.25" Oxygen III Narrowband Filter

SKU CH-WQJE-WXVS1

Isolates the 496 and 501 nm oxygen lines from planetary and emission nebulae while blocking the 400 to 700 nm visual spectrum to increase contrast and eliminate coloured halos around bright stars

  • TypeTelescopes
  • ColorBlack
  • FeaturesThe Oxygen III 1.25 Inch Narrowband Filter isolates just the
  • Isolates 496 and 501nm oxygen lines for nebula detail
  • Blocks 400–700nm spectrum to remove light-pollution glare
  • Ultra-hard vacuum coating prevents coloured halos on bright stars
  • 25-inch thread fits standard astronomy eyepieces
  • Boosts contrast between night sky and OIII emissions

Precision Oxygen III Filter

The Celestron 93623 is a 1.25-inch narrowband filter designed for astronomical observation. It isolates the two doubly-ionized oxygen lines at 496 and 501nm emitted by planetary and emission nebulae. This tool serves visual observers and astrophotographers seeking enhanced contrast on specific deep-sky objects.

Ultra-Hard Vacuum Coating

The filter features a durable ultra-hard coating applied through advanced vacuum deposition. This layer blocks the entire visual spectrum from 400 to 700nm while transmitting the target OIII lines. The precision engineering eliminates unnatural coloured halos around bright stars that occur with less sophisticated filters.

Suits Nebula Specialists

This filter suits astronomers targeting objects like the Veil, Ring, Dumbbell, Crescent and Orion nebulae where OIII emission is strong. It is not for general broadband viewing or galaxy observation where broader spectrum transmission is required. Buyers needing a filter for light-polluted broadband imaging should look elsewhere.

Highlights

  • Isolates 496 and 501nm oxygen lines for nebula detail
  • Blocks 400–700nm spectrum to remove light-pollution glare
  • Ultra-hard vacuum coating prevents coloured halos on bright stars
  • 25-inch thread fits standard astronomy eyepieces
  • Boosts contrast between night sky and OIII emissions

Specifications

BrandCELESTRON
TypeTelescopes
ColorBlack
FeaturesThe Oxygen III 1.25 Inch Narrowband Filter 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.. Each filter has an ultra hard, vacuum-deposited coating carefully designed to block all of the visual spectrum ranging from 400 to 700 nm.. This eliminates the un-natural colored halos surrounding bright stars common with Oxygen III filters of a less sophisticated coating technol...

Questions about this item

Will the ultra-hard vacuum-deposited coating on the 1.25-inch filter need re-coating or replacement over time?

The durable ultra-hard coating is applied by vacuum deposition and is not a consumable layer; it does not require re-coating or scheduled replacement under normal use.

What spectral limit defines the edge of the filter's blocking range during long imaging sessions?

The coating blocks the entire visual spectrum from 400 to 700 nm, so the 400 nm and 700 nm edges are the hard limits that determine how much unwanted light is rejected.

Does the filter housing or glass retain enough heat to affect focus during all-night operation?

The thin 1.25-inch filter glass and metal cell reach thermal equilibrium quickly and add negligible heat, so they do not cause focus shift during extended sessions.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.