On Dec 21, 2018, Chris L Peterson wrote
(in ):

On Thu, 20 Dec 2018 21:15:38 -0600,
wrote:

On Dec 19, 2018, Chris L Peterson wrote

What it would look like if it were brighter, or our eyes more
sensitive, isn't a simple question. The gamut of the sensor in the
camera is quite different from that of our eyes. The color is coming
from several fairly narrow emission lines produced by CN and C2. Those
lines lie in violet, blue, cyan, and green parts of the spectrum.
Because they are emission lines and not a continuum, the color that
gets rendered by any camera is very sensitive to the bandpass of the
RGB filters in that camera, and their crossover points. So different
images of the comet will show a range of colors, typically from the
blue side of cyan to the green side.

Ah, yes, I understood most of that before I asked, but had not yet put it
all
together. But that really is a beautiful green color. I know that even if I
get to see it my little 5” is never going to show much, if any, color. But
it really has to clear up someday, I hope.

Indeed, aperture is irrelevant. No amount of aperture can ever
increase the surface brightness of an extended object beyond what we
can see with our unaided eye. Given the size of this comet, it is best
viewed at low magnifications, and therefore there's no advantage to
more than just a few inches of aperture. (But aperture is critical to
good imaging, as it allows for shorter exposures and therefore a
better capture of this fast moving body.)

I agree. As for the speed of this comet, I had noticed that in David’s 4
shot stack where he pointed out that it was not a tail but movement between
the shots. I was really surprised to see that it had moved that far in, I
believe part of a night. I realize that when they are close comets are
normally moving quite quickly. Well depending on the geometry of course. But
so surprising to actually see it in the sky, where things seldom move fast.

--
Harry F. Leopold
The Prints of Darkness (remove gene to email)

“He's so dumb he moves his lips when someone ELSE is reading.“-Doc
Smartass