Celestron Oxygen III Narrowband Filter - 2-inch
In order to effectively observe the faint photons of OIII light, required for detailed views of the Crescent and Orion Nebulae, the Viel, Ring Dumbbell and other celestial objects, you'll require the Celestron 2" OIII narrowband filter. The filter has been designed to isolate just the two doubly-ionized oxygen lines (496 &501 nm lines) emitted by planetary and emission nebulae while blocking the rest of the overall spectrum of light. This filter achieves extreme contrast between the faint photons of OIII light and the black sky background.
The Celestron 2" OIII narrowband filter has been strategically designed to block all of the visual spectrum ranging from 400 to 700 nm and has an ultra hard, vacuum-deposited coating. The result is an elimination of the un-natural colour halos surrounds bright stars, common with cheaper imitation OIII filters.