Alex,
Re the noise issue, stacking improves the s/n ratio quite a lot as you know.
I have added a couple of small clips of the corner of my EC image to illustrate the difference. the first is a single 90 sec frame and the second is 12 frames stacked in Registax. I hope these come out clear enough to show the improvement.
Please ignore the spherical abberation in these images, that's another issue I am trying to work through (don't you just love this hobby !!).
