Celestron Oxygen III Narrowband Filter - 2" Round Mounted - 93624 GPS The SkyMaster Series binoculars are

The SkyMaster Series binoculars are built to provide years of magnificent views of the world around you and the heavens above

A complete system of adapter rings enables cameras to be directly (and rigidly) close-coupled for afocal projection

94") to work well in binoviewers and spotting scopes

or combinations with simpler interference filters

Blackened lens edges and internal anti-reflection threads tweak the last bit of contrast for maximum image detail

Celestron Oxygen III Narrowband Filter - 2" Round Mounted - 93624 GPS The SkyMaster Series binoculars areAbout the Celestron Oxygen III Narrowband Filter 2" The Celestron OIII Narrowband Telescope 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. The result is extreme contrast between the black sky background and the faint photons of OIII light needed for detailed views of the Veil, Ring, Dumbbell, Crescent and Orion nebulae,