Let the hive mind of Engadget get that for you.
"We need a digital camera that can be switched on and fire off that first shot fast. It's not a commonly tracked statistic on any review site, and nobody seems to have this information for every camera. We were hoping other readers could inform us as to what small digital cameras can fire off their first pics in under a second (ideally under half a second). It needs to be small, but mostly, just really quick in operation. Thanks!"
I was all set to purchase a Canon 5d Mark II but not after reading about some focusing issues I am not sure. I really want to have a full censor and it seems that the Mark IV is cropped versus the 5d. Is there any way that Canon could add some Firmware to affect any focusing issues? Please add any comment regarding "Canon 5d Mark II versus Canon 1d Mark IV." that might shed more light on the focusing and censor size. Thanks!