Originally posted by Gimbal Ricehigh, pressing a button twice as fast as one can is NOT a test of ones reaction time.
I admit that it is NOT if *strictly* speaking. But what I'm suggesting to check something similar just for reference. At least, we know how quickly our fingers can move. :-)
To do formal scentific measurement, we must have a steady moving object and set a line where when the object is moving pass thro it as we can see the moment, we press the shutter release button and then the displacement in the final test shot is measured. Having known the velocity of the moving object, the measurbator can then know the delayed time lag.
But then we are not psychologists to study human reaction times, are we? ;-) (Um, I'm only interested in measurbating DSLRs, you know ;-D)
Quote: Have to say that 0.181s is a bit slower than it feels, I wonder how they measure it. ( I'm not question it though.) A free falling object travels about 0.16meters in that time. A quick test with a mirror, pressing the shutter and dropping an object at the same time confirms it roughly. (Actually the test gave a little shorter time but then there was a human involved.)
It's actually not very slow, but not fast as well when compared to the whole crowd. The K100D is actually faster (as I have told here for several times according to my own experience previously).
In Single AF mode, prefocused but for "full AF", the K10D is actually the slowest amongst the "normal" DSLR, except the Sony and the Olympus, which IMHO is actually too slow to be acceptable.
I bet most of us uses Single AF mode more frequently than all other modes (unless the user has only MF lenses), so this "full AF" timing is crucial for taking a shot with a critical timing.
Attached is an example of mine, the shot was taken with a MZ-S in Single AF mode. I saw the bird was running suddenly and I turned on the camera immediately and there was indeed very little time lag for the AF and the camera system (mirror up to shutter opening) and so I was still able to take the bird. The bird is indeed running very fast. With another Pentax DSLRs, I am really doubt I was still yet able to take the shot, owing to the longer time lag, especially in Single AF mode (but then it's the most commonly used mode).