Dan, I tend to agree with you about internal reflection. So, I went to the link you posted and started reading. Frankly I got bored and couldn't believe how many people had to put in their 2 cents. Like they say, opinions are like $%#holes. Everybody has one, and they all stink. If I was experiencing the problem consistently, I would contact Canon and have them form a solution or explanation. These guys and gals although NOT rocket/camera scientists, are trained, have every concievable piece of equipment Canon makes, and also run into all sorts of odd problems. Thanks for the link though, it was interesting for a short time.