Askar 0.75x 91F Reducer (ASKAR91FR) newtonian even when tested with f/4

even when tested with f/4 scopes

The result is that both the ALP-T dual band 5nm Ha&OIII and SII&Hb filter creates a superior signal-to-noise ratio and better contrast in your OSC images

Our unique two-sided planisphere has been in print for over 35 years and no chart is more respected or recommended

Your Celestron Origin Mark II system comes complete with everything you need to become an instant astronomer:

Askar 0.75x 91F Reducer (ASKAR91FR) newtonian even when tested with f/4The 0. 75x reducer can bring Askar 91F's focal ratio down to F 5, providing not only a faster focal ratio but also built in field flattening correction. The shorter focal ratio delivers a wider field of view and a faster exposure time, making it ideal for capturing large areas of nebulae, star clusters, and faint, fast moving celestial objects. The 91F 0. 75x reducer adopts a triplet design and supports a 44mm full frame image circle. The back focus