Equipment:
-Celestron Omni XLT 127
– Sky-Watcher EQ5
-reducer Meade f\3.3
–Baader MPCC II
-ZWO IR-cut
-ZWO 290 MC.
Processing: Autostakkert 3 (200 frames per 15s, gain 360, dark frame substaction), Fitswork.
Location: Russia, Anapa, backyard
I decided to experiment a little with shooting on a small Schmidt-Cassegrain Celestron 127 XLT. I have a Meade f \ 3.3 gearbox that allows me to increase the telescope’s speed from f\10 to f\3.3, however it only works with small sensors and with a large reduction ratio there is a noticeable coma (stars in the form of birds). I also have a coma corrector for Newton’s Baader MPCC II telescopes. I simply attached a corrector to the reducer and connected the camera to the corrector through the T2> 2 adapter. The appearance of the stars improved noticeably, although it is clear that there is some distortion. The overall reduction coefficient turned out to be about 3.
Below are test images of the M57 nebula without a coma corrector and with a corrector:
