Optolong L-eXtreme Dual 7nm Ha/OIII Narrowband Filter - 2" Diagonals and it has a 45

and it has a 45 mm wide Vixen type dovetail plate for mounting

high speed mode

25" Binoviewers package out there

The finely made glass lens acts as a beamsplitter to combine the natural sky background with the superimposed red pointing "star

This Celestron 12-36x 60 mm LandScout Spotting Scope with Smartphone Adapter features a rugged

Optolong L-eXtreme Dual 7nm Ha/OIII Narrowband Filter - 2" Diagonals and it has a 45The L eXtreme filter from Optolong is 7nm dual band in that passes Ha and OIII emission lines. The advantage of the L eXtreme filter over the L eNhance, which is a tri band filter, is that there are no transmission between the H beta and OIII lines, as there is no nebula emission lines there. In this case, it isn't letting light pollution come through so that maximizes a nebula's signal and makes the sky background darker while imaging. The L eXtreme