Digital Light & Color

Thanks everyone for offering such a varied set of approaches. The one I like for my particular situation is Dieter's suggestion. Really easy to get exactly what I was looking for.

This might sound almost too easy, but for some reason, I am not getting it as easy as I feel it should be. I need to crop an image to 15x10, but it will be mounted in a frame with a passe-partout that shows 13x8.6 (all centimeters BTW). So I'm looking for an easy way to crop to one aspect ration, bu...