I dusted off an old telescope, a 127mm Maksutov Cassegrain, mounted it on the Atlas EQ-G, and attached the ZWO ASI224MC camera. Having no provision for autoguiding this telescope, I decided to acquire a lot of very short unguided exposures and see what I could make of them.

This image combines 984 one second exposures, acquired at f/12.1 and a focal length of 1540 mm, along with 100 bias frames. Imperfect collimation of the primary mirror is evident, along with a little bit of coma and chromatic aberration. But the low read noise of the ZWO ASI224MC continues to impress me. Only a mild noise reduction process was required after the frames were calibrated, registered and combined.

The frames were processed in PixInsight, using a "CFA drizzle" technique. PixInsight's new Arcsinhstretch process really helped to preserve the star colors.