Highlights
- The 1-1/4" OIII 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 700nm This eliminates the un-natural colored halos surrounding bright stars common with O III filters of less sophisticated coating technology.