User blog comment:KATANAGOD/Black Ops II Free Weekend on Steam/@comment-4921618-20130222074352/@comment-25496444-20130223222536

The MW2 camo pics I've taken (examples here and here) were taken with F12. If you go to Shift-Tab in-game, under the Screenshots tab you can press "Set shortcuts" where there's an option to have a compressed copy somewhere on your hard drive.