Having a play with my traveller the other night - it's an Orion 4" F6 achro shorty - and just whacked my Canon 1000D on it to see how bad the CA was.
As you'll see from the attached, it's pretty bad but the thing I'd appreciate someone else's thoughts on is the curious artifacts I get when stacking images taken with the Canon.
There is a really pronounced streaking running diagonally through the whole image. To demonstrate, here is a section of an image after stacking. Also shown is a small crop from the stacked image and a small crop of the same area from an unstacked JPG taken from one of the individual subs.
It seems to me that the artifact only appears in stacked images and not unstacked - so it would seem to be introduced by DSS.
I wonder if anyone can suggest what combination of DSS settings might be the cause or cure?
Heavy noise in the red channel. I had this problem in the past with a Pentax DSLR and a Nikon Coolpix. Not a DSS problem but a dat problem. Stacking makes the problem worse. I'll try to dig an old shot with the same problem.