There is a lot of misinformation regarding the option “Enable RGB Full Range” located in the Display Options menu in the PlayStation3.
If you ask in a lot places around the net, the common answer it’s that you should have it enabled no matter what, because everything is darker, the colors are more “vivid” and the image is no longer “washed out”, but this it’s totally wrong. The reality is that you lose all the detail in the shadows or dark places and the colors are over saturated if your HDTV doesn’t support it.
Almost every one of the Hight Definition Televisions in the market are made to work only with RGB Limited Range for legacy support reasons. That means that they only display the range of color from 16 (Black) to 235 (White) instead of the Full Range (0 to 255). On the other hand, most, if not all, of the PC monitors are capable of displaying the Full Range because they are not limited by the Television standards.