Quote:
Originally Posted by muletopia
A good one John, the stars are focused and the tracking looks good. But the stars, say upper right in your image, show tailing on their right. An optics problem? The flattener not working to the corners of the image?
I do like your picture.
Chris
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Chris, so i did some experimenting, and it would seem the issue is back focus.
That photo was taken at the 105mm backfocus.
I reduced the backfocus to 85 by removing the filter drawer and inserting the filter to the camera and the issue was much better, but still slightly there, easy to crop out though if i wanted to.
With the celestron OAG i cant get any closer backfocus without finding an appropriate SCT to M48 adaptor that will screw onto the reducer, the thread on all the ones i have seen are not long enough.
The only other option is to go the ZWO OAG-L but then i cant use my filter draw and have to get a filter wheel