I've been focusing my studies on rendering and computer graphics lately and i've discovered that you HAVE to do alot of "cheating"  to get photo real results.

Check out this article on "The Science of CG".  This will give you a place to start when trying to understand physics and what your renderer is doing....

www.subdivisionmodeling.com/forums/showthread.php

Next head over the this place and read up on the "Linear Gamma Work-Flow".  You're going to find out that everything you been doing ( and most people for that matter) is WRONG!  - in a big way.

www.lysator.liu.se/~zap/lwf/

and finally, for something really cool,  check out the "Pigeon Impossible" podcast on Youtube and it's blog...   Here, Lucas Martell tells you about working on his short film and all things he went through to try and make it perfect.   Starting with Multipass Lighting....

www.youtube.com/watch

Doing Photo real rendering ain't for the faint of heart...

take care

P.S.  maybe the word "Realistic" is kinda like the word  "Truthy"....