Tonight it was a perfect night for optical test of my new glass.
Attached are the 200% crops from one 5 sec exposure at full aperture, f/2.8.
For comparison, I also attached 200% crop from corner taken with Tair-11A (the lens I was very proud of).
While in the centre both of them are almost equally sharp (that means - sharp), Tair shows significant coma in corners.. also it is worth mentioning that the Tair shot was taken at f/5.6...
Canon 200mm FD S.S.C. is significantly better in corners, even at full aperture
Total cost: around $300
The next step is addition of lever to control the diaphragm.. (I expect a significant improvement at 1 or two stops down) and I will have a very good lens for narrow wide-fields
