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11-04-2008, 03:22 PM   #16
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QuoteOriginally posted by dafiryde Quote
oh. i now understand what you said when you said it the first time
but do you think there would be a benfit over the 1.4 vs the 2.8 in low light focusing speed

Dave
I'd have to do some searching but I'm pretty sure there is a limit to the amount of light the camera can use to focus. In other words I think the camera doesn't receive anymore light from a 1.4 lens then from a 2.8 lens.

There was a pretty large thread about this either here or on dpreview some time ago but I can't seem to find the thread.


John

11-04-2008, 04:46 PM   #17
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what brought this up, was when i attended my moms 80th birthday and the area where the function was held , developed a low voltage problem. everyone did not mind as this made the lighting a nice warm effect.

my problem was the 50-135 was out of the question as the focus hunted back and forth. the 16-50 hunted way less, but was fustrating waiting for focus to lock. today i am sorry i did not use the onboard flash as this gives off small bursts of light so as the camera would have something to lock on, but then again the top of the lens comes out in the picture. the spot beam on the 360 flash and nothing is the same , some times i wonder how compatible that flash is to the k10d.

so i wonder now if the 50 1.4 would have saved the day

Dave
11-05-2008, 12:33 AM   #18
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QuoteOriginally posted by dafiryde Quote
QuoteOriginally posted by Quicksand Quote
Some of us suspect that it would focus better (more accurately, possibly faster) if it were stopped down to (e.g.) f/2.0 or 2.8

as far as i know, the lens does not stop down to the value of the set aperture until the shutter button is depressed, which is after focus lock is confirmed.
Precisely. And because of this, the camera is stuck trying to perform AF with the lens at 1.4, where the lens is kind of low in contrast, rather than focusing with the lens at 2.0, where there might have been more contrast.
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