Last week my Canon lens-to-SBIG ST8300M adapter arrived. Beautifully machined, it is. Expensive, it is! I tried it out with my 50mm f/1.8 and 17-70mm f 2.8-f4.5 zoom lenses. Images showed nice stars at the center of the fields, but progressive defocus toward the edges. I should not have expected anything different, since I had the lenses wide open.
How does one stop down a fully automatic Canon lens? Turns out it's easy, just follow these instructions. They work for me. My thanks to Haje Jan Kamps for posting them at pixiq!
Now if it would clear up for one night I could test the improvement.
I also upgraded to ImagesPlus 4.5, but am having a little trouble getting my old serial number to complete the registration. The always-helpful Mike Unsold, creator of IP, is on the case, so I should be up and running soon.
