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Getting ther Ice.
First and very importantly is your scope well colliminated.
Hi resolution shots require the very best incollimation to get good results.
Low power stuff and visual viewing you can get away with a moderatly aligned scope.
But you need to have a Newt as good as possible includeing focuser alignment especially in faster newts.
Also you need to use only shots from the centre of the FOV as coma will degrade images from the outside of the Field.
In a fast scope you only have a few millimeters diameter in the middle that are concidered coma free. The longer F no the bigger that spot gets and the more forgiving on imaging.
So that's one reason you see long F6 + newts.
It may be all that is stopping even better shots.
Can you take an inside and outside of focus shot of sirius for me(like in my review) and send it via e-mail to see what your alignment is like. You can make it a large file size in the e-mail.
Use a 2 X barlow to get high power with the web cam for the test and turn your focuser in and out to get a similar result as in the review.
Again try to use only the centre of the field in the test.
If while doing the test you move the star to the outter part of the field have a look at what it does to the image circles and you will know what coma is all about.
I have tried over the past few night shots of Saturn but turbulance in the atmosphere has been bad with the heat and viewing hindered with dew. my shots did not turn out much better than yours.
It can be frustrating but don't give up, you will crack an excellent image soon.
Tell me when you extract all the frames are any much clearer than others as they drift across the FOV?
Mark
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