Originally posted by K-9 1 subject in a shot, either person or building. sky background in one shot, studio background in another; etc etc. The building, person, obejct all remain as the focal point within the shot, but everything behind it changes. Is there a program that can stitch together within the photo (ie the central subject) because I know most stitching programs rely on everything being the same at each joining edge, and preferably overlapping. Can any program piece together edges that do not match, or will I have to do it all manually?
Ok, if I understand you now, you want to take a subject (any single subject) and superimpose it over multiple backgrounds, yes?
CS5 has some 'content-aware' masks, but I've not worked with them. If I were going to try and do what you're describing with an image *I* was going to shoot, I'd green-screen the person, then mask them out using colors; once you've got them masked out, you can drop 'em on anything.
There are several software products designed to help you mask out items - in the instance that your subject is a building, say, one can't shoot THAT against a green screen! - easier than the magic wand or manual painting in PS. Topaz Remask seems pretty good - I've only played with the demo.
Still, you're probably going to get your best results by doing it manually with the quick-mask mode and the magic wand.