I wanted to post this before I lose track of it again.

I get questions about lens sharpness from time to time and my first question is always “Have you run your lens through a focus test?” Invariably the answer is no. To which I always reply “do some focus tests under controlled conditions and then evaluate the results.” So HERE is where you can read up on how to do the test with links to a downloadable focus test chart that you can print and glue to a box or board or something flat. So if you think your lens is not focusing properly TAKE THE TEST :)