Thanks Raoul!

That's a good question about the shutter speed. The short answer is that, all else being equal, higher shutter speeds usually eliminate most/all camera movement which results in better photography.

But to be precise, I don't know all the variables for your shot. I'm told to turn off vibration reduction (VR) when using a tripod with my Pentax, but even with mirror lock-up - which I used - there is always the possibility of some remaining tiny vibration coursing through the camera/tripod system - to say nothing of the wind! - so I left the VR on for my shots.

You didn't specify if your 300mm zoom lens has image stabilization, and I don't know Canon's recommendation for shooting with a tripod, but at 1/4000th you may have been working hand-held, for all I know, so there are many variables. It's worth noting that, according to testing data I've seen, lens mounted shake-reductions systems (Canon, Nikon) are somewhat superior (stop or two) to body (sensor)-based systems like my Pentax (also
Sony and Olympus).

One thing I forgot to mention: unless you have a really big, massive, ultra-sturdy tripod, I recommend deploying it close to the ground, i.e. without the legs or "neck" extended, as this will result in a steadier platform, but more difficulty focusing in some situations, and that was the case for my shot with the moon relatively high in sky. Also, it was cold here, and as you note, getting what you see is really a challenge, especially if your eyes are watering.

Also worth noting, prime lenses, as opposed to zooms, are much crisper. If you use a long zoom, so I understand, you'd probably do best to back off a bit from the maximum focal length, to about 270mm for a 300. Additionally, for most lenses - zoom or not - stopping down to about f8 seems to give best results, but of course that will take away from that high shutter speed.

With photography, like chess, "...the mistakes are all there, waiting to be made." I don't know that I've yet made them all, but I'm working on it. At least with digital we can pitch our mistakes, the only cost being our time, and often, our tears if there is no success for our efforts on that occasion. Still, we learn. Nevertheless, some opportunities come along only rarely, so the best advice is to take many, many shots, learn all the tricks, and hope for a little good luck.

Thanks again for your kinds words. I'll close with the final thought that, before processing, my image didn't look much different from yours.

S