The Baader premium-grade 1.25" OIII filter (10nm bandwidth) is perfect for observing faint nebulae in light polluted areas. It works well in fast optical systems from f/10 to f/2.8.
Great at enhancing the contrast of OIII nebulae, this filter is excellent for use both in light polluted areas, and at dark sites.
These filters block the IR wavelengths. They will not produce halos or reflections.
The glass substrate is finely optically polished plane parallel, providing 1/4 wavefront over entire surface.
Multi-layer dielectric coatings are plasma-assisted and ion beam-hardened using the latest technology
The Baader Planetarium Narrowband 10nm OIII Filter coatings will never degrade from normal use or normal cleaning.