I did this test to satisfy myself that the 'common' belief that "the IS of the 70-200f2.8IS can cause unsharped image if the IS is not turned off at slow shutter speed or on tripod" is not true. The problem is that the IS takes times (i.e. 1/2 to 1 sec, depends on lighting condition?) to stabilize under less than ideal lighting. If the image is taken BEFORE the IS has a chance to stabilize and the shutter speed is too slow to avoid camera shake, you end up with unsharped image due to camera shake. In my test, I gave the IS lens a "2 sec delay" (i.e. half press the shutter to activate the IS) before fully press the shutter to take the shot in order to give the IS a chance to fully stabilize.