I looked at some of your stuff, and you're not getting the out of focus problem because your characters are, for the most part, butt-up against the backdrops, but they do flatten out. I thought Guardian was as it was downloading, until I got to the goat's legs. Then I saw the figure was 6-8 Poser feet from the backdrop. I'm talking about scenes much wider, with multiple characters, 10-20 feet from the backdrop. If you still have the Aria's dream file, try re-rendering with a 35 or even a 25 focal length. I think you'll see what I mean.