Bert, all,
that's why I always hold on to old data
I've been doing the upsample to my DSI II stuff for a while now
pre-stack because it seems to work, but only on good nights with
lots of subs, as has been mentioned.
I don't really understand the maths but I know it works for the
planetary guys as Bird says, so why shouldn't it work for LX
The DSI software has the dither function as an option and explains
a bit about star overlap over a pixel grid and interpolation.
Here is an example of my results when I upsample 2x with a Bspline
algorith before stack.
Even though the input raws are done on a night of EXCELLENT seeing
it only works when there is some slight change in frames due to tracking
and seeing in combination. I don't know if it is a combination of
the focal length, sub length (5s in this case) and arc sec per pixel
but the result definitely improves fine detail.
Steve