[Everlast]

Casio QV-R40, R51同部分數碼機仔都聲稱自己擁有僅0.01秒既快門時滯, 但係連Nikon D2H都係得37ms (0.037秒), 那麼它們是有取巧之嫌嗎?

[FF_Dom]

Casio QV-R40, R51 claimed 0.01 s is after focus, from half press to full press the button., right?

And the major shutter lag is due to pre-focus, ie. from no-press to half press the button.

[ninekit]

both are right, since the casio use electronic shutter, so it can be much faster than conventional SLR / DSLR which has a lag for the mirror to flip up and down, even after pre-focus.

however, i also believe the D2H will focus much faster than the Casio.

so the total lag = focus time + pre-focus shutter lag should still favour the D2H.

[呀超]

D2H 快唔過 R40 就死囉！

[ninekit]

there is no such "absolute" thing in the world. I have played a bit my friend's Casio old Z2. i bet the response time is faster than D2H, as it use a focus free design. :-)

[afan]

This diagram can clarify the definition of shutter lag

http://www.ricoh.com/r_dc/caplio/g4wide/features/img/index_5.gif

[ninekit]

thanks afan for the graph explanation.
as far as i know, i lot of manufacturers refer the 快門時滯 to only the time between shutter pressed halfway to exposure, i.e. time between exposure and pre-focus, and i am sure the CASIO quote is that, and thats why it can be so impressive.
as far as i know the shortest shutter lag achieved for production camera is D2H (even better than F5), its only 0.002s when mirror lockup is activated. next is the film camera EOS 1n RS, 0.006s, it can be that fast because it has a fixed mirror, so no need to wait for it to flip out of the light path before exposure begin. then the 3rd place is a 1989 model, EOS RT, which use the same semi-transparent mirror and achieve a lag of 0.008s. Then the next I know is the Leica M6, full mechanical rangefinder with shutter lag 0.018s.
These numbers are relevant, but not too relevant in whether you can take a great picture or not, just sharing for fun.