Clear night: More M27 time and some other targets

The moon has set and, with DST over but no snow cover yet, it is surprisingly dark in my back yard. It’s clear and not too cold — about 5 degrees.

Gathered 2 more hours of data on M27, this time in 15-minute subs. I’ve bumped this up from 10-minute subs just to see the effect. I would expect slightly deeper results, and slightly better S/N, than with more shorter subs. On the other hand, the longer the exposures, the greater the chance that something like a passing plane will ruin them. So I’ll try 15 and see how that works, and maybe push even longer for the next run.

Watching the guiding graph, I note that RA guiding is still tending to oscillate back-and-forth across the zero axis, so I have tried turning the x-aggressiveness down a bit, to 60%, to see if it can further smooth out the curve. Watching the results for a couple of minutes, it does seem to have resulted in a flatter error curve.

While the data collection was running, I took a look at the G2V calibration images I collected the other night. On first approximation, the balance figures seem to be RGB 90-100-116. I’ll try that the next time I do a de-Bayer.

Following 2 hours of m27 data collection, I did a quick snap of M15, to experiment with exposure levels suitable to leave detail in the core, . . .

and an hour of M1, the Crab Nebula, just rising low in the East (and viewed through poor seeing from neighbour’s chimneys).