See this side-by-side test:-http://forums.dpreview.com/forums/readflat.asp?forum=1036&thread=37969644ISOK-5K-r100200400800Everything used and the settings are all the same except for a different body. And of course, the test environment and test target are the same, too. It is easily seen that the higher ISO the user selected, the more overexposure resulted with the K-5. Do note also the
