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03-17-2009, 04:25 PM   #31
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QuoteOriginally posted by simico Quote
And with the tiny dark viewfinders MF often won't work either in these situations. Last weekend I also tried to shoot some small birds sitting on trees and in most cases neither camera's AF, nor I with MF could lock focus on the bird. In most cases the AF locked focus on limbs behind/in front of the bird, in the MF attempts the birds looked like sharp in the tiny viewfinder and blurred (out of focus) on the pictures. Honestly, these tiny viewfinders are not usable for MF on small, distant subjects.
The focus screens themselves aren't much good for manual focus. I bit the bullet and bought a Katz-Eye last year.
Probably the best accessory I've ever bought for a camera.

03-17-2009, 07:56 PM   #32
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QuoteOriginally posted by FHPhotographer Quote
Well, I've tried it but I guess I'm in sort of denial that AF could be that imprecise.
Well, it focuses very *precisely* on whatever the heck it feels like focusing on that happens to be within range of the AF sensor. What's imprecise is selecting *what* the camera focuses on, but the focusing itself is (or should be, anyhow, assuming no FF or BF issues) very precise.

QuoteQuote:
So, there is nothing to be done with AF, any any camera, other than hope for the best? Maybe it's the old dancing dog analogy again... if you see a dog dancing on its hind legs don't criticize that it dances badly, just marvel that it can dance at all.
Yeah, that's about it :-). In practice, it's often good enough - the intended target is often as big as or bigger than the sensor, and even when it isn't, the camera *might* happen to choose your target and not whatever it behind it or next to it. If you are careful to select the appropriate focus point 0 or use center point & focus-recompose, chances are pretty good you'll get what you want. When you don't, you can always try again, maybe it will pick differently. But that's why I am reluctant to buy anAF lens without quick shift - there will *always* be times when the AF system simply will not choose the target I intended (like a bird in a tree) and I have to override it.

BTW, in general, the more focus points a camera has, the *smaller* each will be, and hence the easier it is to pinpoint the focus. At least in theory.
03-18-2009, 10:19 AM   #33
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QuoteOriginally posted by Marc Sabatella Quote
But that's why I am reluctant to buy anAF lens without quick shift - there will *always* be times when the AF system simply will not choose the target I intended (like a bird in a tree) and I have to override it.
Does focus-by-half-pressed-shutter need to be disabled for quick-shift focus in AF-S/C? It seems like AF kicks in all over again otherwise, once I press the shutter overriding on-the-fly, quick-shift focus adjustment.
03-18-2009, 11:25 AM   #34
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QuoteOriginally posted by wasim_altaf Quote
Does focus-by-half-pressed-shutter need to be disabled for quick-shift focus in AF-S/C? It seems like AF kicks in all over again otherwise, once I press the shutter overriding on-the-fly, quick-shift focus adjustment.
Half-press and *hold* the shutter while tweaking focus manually, then - without ever letting up on the half-press - press the shutter the rest of the way to take the picture. Same process as focus-recompose - the "hold" is essential, or the camera will of course refocus when you take the shot.

03-18-2009, 05:27 PM   #35
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QuoteOriginally posted by Marc Sabatella Quote
...the intended target is often as big as or bigger than the sensor, and even when it isn't, the camera *might* happen to choose your target and not whatever it behind it or next to it.
I've decided my K10D can "see thru" people with dark clothing. It nearly always focuses on something in the background rather than the group of people filling the frame! (and this is using the centre AF point, not letting it decide itself) I do not trust it at all!

cheers, Nige
03-19-2009, 09:32 AM   #36
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QuoteOriginally posted by rpriedhorsky Quote
No.

Or at least, not for me. You gain an extra 5mm or so nose room, which wasn't significant for me.
That's unfortunate. There is so much space between the eyecup and my eye that I get light getting in thru the gap. Any other after-market eyecup available out there?

Thanks for the link to the AF paper, btw.
03-19-2009, 10:01 AM   #37
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QuoteOriginally posted by HGMonaro Quote
I've decided my K10D can "see thru" people with dark clothing. It nearly always focuses on something in the background rather than the group of people filling the frame!
A camera needs a hard edge with contrast to focus, so yeah, it will often go out of its way to find something in the background if it doesn't like what you have in the foreground, and people wearing dark clothing often fall into that category. If the people *do* actually cover the entire AF sensor you have selected, the camera will not be able to look at the background, but it might hunt for quite a while trying to lock focus on the dark clothing, and perhaps even just give up.
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