Baader F/2 Highspeed Filter H-Alpha Size::31mm Secondary Mirror Obstruction by Diameter:

Secondary Mirror Obstruction by Diameter: 36%

CPC 925 is currently deployed aboard the International Space Station) and astrophysicist Stephen Hawking

detailed objects that pop off the black sky background with superior contrast

You can spray the fluid directly onto large optical surfaces

Baader F/2 Highspeed Filter H-Alpha Size::31mm Secondary Mirror Obstruction by Diameter:Baader F 2 Highspeed Filter H Alpha CCD imagers will find that Baader's new Narrowband 7nm H Alpha pass filter delivers the absolute highest contrast deep sky images of H II regions, all with the shortest exposures possible. Its narrow 7nm FWHM bandwidth has a transmission at H Alpha of over 90%, while completely rejecting light pollution. The high optical quality of the Baader 7nm H Alpha filter guarantees no loss in sharpness or contrast. Each