2Inch O-III Filter greatly enhances contrast during visual observation of gaseous and planetary nebulae in all sky conditions; astrophotographic 2inch filter allows high-contrast imaging even in areas with strong light pollution
Especially useful for large aperture telescopes through which the light of the Moon can be extremely overwhelming; allowing just for the Double Ionized Oxygen lines between 496nm to 501nm to pass through at 95 percent
Completely blocks virtually all other visible wavelengths of light so views of nebulas are optimized; increases contrast through selective filtration-Anti-reflection coated to prevent glaring and ghosting
Image erecting BAK4 prism with anti reflection coating; High accuracy and high light reflection prism; Internally matte blackened and threaded for no internal stray light reflection; 1.25 inch adapter with brass compression ring included
Entirely aluminum black anodized with smooth finish; if there is any problem of focusing due to the light path for a few telescopes; please feel free to contact us for help