Antlia 4.5nm H-Alpha Edge Series Filter - 31 mm - HA-EDGE-4.5NM-31 Focusers and 102 telescopes

and 102 telescopes

The design minimizes aberrations and distortions

While this filter is similar to the D1 duo-narrowband filter

and threaded metal covers on the lens assembly to protect your investment from dust and scratches

but also three accessories (reducer

Antlia 4.5nm H-Alpha Edge Series Filter - 31 mm - HA-EDGE-4.5NM-31 Focusers and 102 telescopesThis narrowband 4. 5 nm H alpha filter from Antlia is part of their Edge series and is of the 31 mm unmounted variety. It is normally used in a 1. 25" 31mm filter wheel, where it drops into place. Important! Not for use when viewing or imaging the Sun! Antlia 4. 5nm Edge Series H Alpha Filter 31 mm Unmounted Antlia H alpha Edge narrowband filters optimize the FWHM (full width half maximum) to a 4. 5nm bandpass. The suppression of optical density (OD)5