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: