Antlia 4.5nm H-Alpha Edge Series Filter - 2" - HA-EDGE-4.5NM-2 60 mm Spotting Scopes and there is also a

and there is also a reticle parallax compensation adjustment to ensure the target and the reticle are on the same focal plane

each pair of glasses is tested before shipment

Suitable for lighter-weight iOptron computerized telescope systems such as the SmartStart series AKA "The Cube

Eyepieces: K20mm 1

and provides an exceptional 7° field of view

Antlia 4.5nm H-Alpha Edge Series Filter - 2" - HA-EDGE-4.5NM-2 60 mm Spotting Scopes and there is also aThis narrowband 4. 5nm H alpha filter from Antlia is part of their Edge series and comes in a 2" threaded filter cell that is designed to be screwed on to the 2" receptacle of your astrophotography accessory, including a 2" filter wheel or filter holder. Important! Not for use when viewing or imaging the Sun! Antlia 4. 5nm Edge Series H Alpha Filter 2" Mounted Antlia H alpha Edge narrowband filters optimize the FWHM (full width half maximum) to a 4.