Why is my picture soft..?

Karel Bata

I've got a pair of Canon 600Ds on loan from a college (for a 3D project), I took a quick test shot using each before leaving them in a locker there overnight. They both have Canon EF 24mm lenses which were set at infinity. The metadata says the exposures were 1/2000 and 1/4000, so there's a stop difference.

Any ideas why is one is so much sharper than the other? I could take it back, but the place is about to close up for the summer and I'd rather fix the problem myself so I can hang on to them for the next six weeks. Any ideas?

arodney

Could be a back focus issue on one.
http://www.learn.usa.canon.com/resources/articles/2011/backbutton_af_article.shtml
Or the mount is screwed up on one.

Karel Bata

Thanks for the reply.

Wouldn't both those problems look like a focus issue - some parts of the image being sharper than the rest? This is soft overall.

MarkR

Can you try another shot with the affected camera?

Karel Bata

I certainly will! I need to get this fixed.

I wanted to go in today and pick them up, but it'll have to wait till tomorrow.