Above is the start of the mosaic. 3 Panels that will probably be six before it is all said and done. Below is just the North America Part, unfinished since I need to get the top of the nebula. Click to see it at 50% of the full resolution.
Comet Erasmus (C/2020 S3) on Nov 22, 2020, 4:50 AM to 5:40 AM. 50×60 sec sub-images captured in SharpCap 3.2, QHY183c at -20C cooling, Gain 20, Offset 200, Optolong L-eNhance filter, Televue TV-85 at F/5.6, dark, flat, bias calibration, Metro area, Bortle 7-8 zone, clear and average transparency, seeing was poor for comet elevation (under 12 degrees.) Star-Freeze version.
New comet discovered in September, 2020 in the morning sky at twilight. Very low and very hard to image from the metro area I’m in. I used an Optolong L-eNhance filter, which helped beat back the terrible LP I had to image through when it was less than 12 degrees above the horizon.
Gain was too high for this project. The over-saturated areas caused column/row artifacts which created dark horizontal bands on either side of the brightest part of the core. It was difficult to deal with in post-processing. Next time, I want to try some low-gain, longer exposures instead to see if the banding problem goes away.
For fun, I combined this image with my M42 project image that included all my best data to date. Here is the results of that mix:
A very dark sky would have made quite a difference for this comet, but to me it is almost too small to be worthy of a trip to the boonies just for this guy. A runt comet. lol
This was taken from a Bortle 7-8 zone in a Metro area with the Optolong L-eNhance filter, my QHY183c camera and Televue TV-85 telescope.
It was moving very fast and exposures of two minutes showed slight trailing. I made a star-streaks version with some 3×5 minute simulated exposures and 4×3 minute simulated exposures. The actual sub-images were 30 seconds and SharpCap was used to LiveStack the simulated exposures. Here it is below:
This was taken before the 1st image, so you can see how far that sucker moved in the intervening time.
“Thor’s Helmet,” aka NGC 2359. First time I ever shot this with any camera. For years I’ve passed this guy up for bigger or better objects nearby, but not on this night. It was a main goal for this night’s imaging session. It did not get high enough to image until 2:00 am here and I took a nap as soon as I started it going. Luckily, I got enough data before sunrise to make a half-decent final image
UPDATE Nov 13, 2020:
More time added with 30×120 sec sub-images at Gain 20, offset 200 to the above. Total time 3 hrs, 22 min.
