Interesting Article on Lens
 

Thought someone might get something from this. I subscribe to the model train online magazines for dio idea's mostly but thought this was a pretty good article.

http://www.trains.com/trn/default.aspx?c=a&id=6664

True, it's interesting. It's stuff one picks up intuitively when taking a lot of pictures with varying zoom, but it's nice to see it illustrated so systematically.