Hi Bert,
Not Bad for "just a test"
And with a full moon too!.
I bet you can't wait to get that camera under a dark sky.
I grabbed your Jpeg and reprocessed it. Focus was not as tight as it could be, but I say that without knowing the limits of your optics at 2000mm fl. There is what appears to be a dust mote in the upper centre (I cloned that out). There was no vignetting as in your other shots. I also notice that image size was reduced. Did you crop or just resize?
I must say that although I only used your jpeg, I am still very impressed with the data that your 5DH is producing. Under a dark sky in winter, it should be sensational!.
Cheers