okay, here are some things you might try. Run your pictures through the noise/desaturate filter. Photos NEVER have crisp lines the way CG does. The images need to be softened just a bit and despeckle does a pretty decent job. Go to gaussian blur if you need more. Desaturate your colors just a tiny bit. Play with your channels palette, try using different filters and adjustments on the various RGB channels. Working in the RGB channels is what most photographers do to adjust photographs. Play with levels and curves to find out what they do. They're extremely powerful tools. Learn the various colors of different kinds of light. There's very very little pure white light in the world. Sunlight is tinted yellow, moonlight blue, indoor light ranges from orange to red to green for flourescents. Your lights should all be tinted whatever color the scene calls for. Not a heavy tint, just a very pale tint. This also applies with artistic work like paintings. Many artists tint the blank canvas a very light shade of the primary color in the picture. This way the entire picture gives the impression of this color and has a coherency, it hangs together and all the parts appear to be part of the whole. Try compositing several renders as well, so that you can get a depth of field effect. Photographs are rarely sharply focused throughout the entire field.

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