"The Three Questions
I get asked a couple of questions every time I publish a graph showing Imatest results for multiple copies of lenses like the one below. Most people understand that some copy-to-copy variation is inevitable in the manufacturing process. Most are surprised, though, at how large the sample variation seems to be. Heck, I was surprised at how large the sample variation was when I started doing this kind of testing.
The three questions I get asked over and over are the same questions I asked myself when I first started seeing these results:
Are you sure the variation is that great?
Can you really see the difference in a photograph?
Can optical adjustment make the copies with the worst results better?
Rather than constantly answering these questions in email, I thought I’d just make a reference post that answers them as completely as I can."http://www.lensrentals.com/blog/2013/09/there-is-no-perfect-lens
A very interesting article.