The 1.25" O-III narrowband filter is specially designed for the observation of gas and planetary nebulae that are emitting light from narrow OIII wavelengths. It distinguishes different contrasts of the wavelengths of light that pass through, giving ideal conditions for the observation of faint super nova remnants and planetary nebulae remnants.
The O-III narrow band-pass filter isolates just the two doubly ionized oxygen lines (496 and 501nm) emitted by diffuse, planetary and extremely faint nebulae. O-III filters work ideally with medium to larger aperture telescopes in the 150mm and larger range.
With larger aperture telescopes, observers will have a better opportunity to identify nebulae objects in the deep sky. It can produce near-photographic views of the illusive Veil nebula which is a difficult target without an OIII filter even from extremely dark skies. The Ring, Dumbbell, Orion, plus many other nebulae also benefit from this specialist filter. The filter is threaded to fit either standard 1.25" astronomical eyepieces and accessories with standard filter threads and is supplied with a protective storage case.
