Thanks APOD for featuring my image!! Very humbled and honored! Glad so many like my image and great discussion as always!
For a little background on my approach to taking this image which might explain how the comet appears as bright as it does I decided to shoot rather long sub exposures for a comet at 5 minutes and a high ISO 1600. I was watching a lot of images come in of C/2016 R2 and thought that with the large FOV that I have with my equipment it might be good to go for longer exposures as the movement of the comet would be pretty imperceptible when it came to stacking. Turns out I was right! If you look in planetarium apps or desktop software and you skip forward in time you'll notice that at this time from our vantage point it's not moving a whole lot in the sky each night. Most of the other comets I've imaged in the recent past shooting 5 minute subs would really smear them since they were all moving in the sky pretty quickly. The nucleus of the comet only moved very slightly in each frame so I wasn't even able to do a proper comet stack in Deep Sky Stacker.
I was very surprised by the color I was able to pull out of the resulting stacked image! With some stretching I was shocked that it appeared even more vibrantly blue than M45!
One thing I was thinking about after looking at this image for a bit I've noticed that the tail may even extend past the FOV to the left, it's quite faint but it seems like more may be visible in a different framed long exposure stacked image. I also see what appears to be a kind of spiraling in the tail that was present in some other images with a more detailed and closer FOV's.
A lot went right when this image was shot, I had excellent seeing/transparency at the Bortle 2-3 site where I was, and I had a really good polar alignment and tracking was perfect. If I had time I may have shot it at 10 minute subs, and may still if I get a chance this month.
As for the visibility through a small telescope I do agree with the editor's, especially if you have a fast scope like the one I shot this with that is at f4.9. I would imagine in a large FOV very fast Dobsonian this comet might be a lot of fun! At the time when this was shot the comet was really close to zenith so I had trouble seeing it in my 20x80 celestron binoculars but I think I saw it very faintly, it's hard to tell since it was hard to hold them steady when looking straight up (I need a bino mount for them
If anyone is interested here is the technical info for this image:
15x300" Light at 1600ISO
Camera: Canon 6D Hutech UV/IR Mod
Telescope: William Optics Star 71 Astrograph
Mount: Celestron Advanced VX
Guide Scope: Orion Mag Mini With SSAG
Capture Software: Backyard EOS
Stacking: Deep Sky Stacker
Processing: Photoshop CC
Date: 2/3/2018 7:16pm - 8:33pm PST
Location: Los Padres National Forest, CA