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09-03-2010, 12:47 PM   #1
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Quick one on AF-C

Just wondering, anyone happen to know if the AF-C setting on a K20d will attempt to continue tracking focus during a longish exposure, or just stay where it was upon release?

I assume the latter, but....

09-03-2010, 01:01 PM   #2
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I don't believe it can track during the exposure. Doesn't the mirror have to be down for it it AF?
09-03-2010, 01:02 PM   #3
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I believe it is locked when the shutter is tripped,

ALthough I have not seen a schematic of the light path, I think the mirror needs to be down for the sensors to work
09-03-2010, 01:17 PM   #4
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K. That sounds right. Hey, what if I used Live View? Which I confess I only ever turned on once, went, 'That's nice,' and switched things to DOF preview.

If she hasn't gone by now, I'm attempting to photograph a very patient, but cool looking, moth in a rather awkward place with a kit lens. I lack camera support that's both tall and bendy enough for this task, thus I'm trying to get the pop up flash, shutter, and my precarious position to coincide.


As you guys may know, I'm not exactly the queen of Macro, here. Thus I tend to try and fake it from time to time. (Also, this moth is very sacked out and will probably remain a while. )


Last edited by Ratmagiclady; 09-03-2010 at 01:23 PM.
09-03-2010, 01:22 PM   #5
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QuoteOriginally posted by Ratmagiclady Quote
Hey, what if I used Live View?
Note that in LV, you need to hold down AF button to activate autofocus.
09-03-2010, 01:38 PM   #6
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QuoteOriginally posted by SOldBear Quote
Note that in LV, you need to hold down AF button to activate autofocus.

Thank you. (I used that.) This LV option really needs its own button, not digging through menues.
09-03-2010, 03:58 PM   #7
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QuoteOriginally posted by Ratmagiclady Quote
Thank you. (I used that.) This LV option really needs its own button, not digging through menues.
If I remember correctly live view is activated with the preview option on the power switch on the K20d. The K7 has it's own button for live view but many other buttoned options have disappeared or been inappropriately placed (for those of us use to the layout of the 10/20).

LV on the K20 is pretty useless, especially for AF. I'm not too jazzed about the AF on the K7 live view either. It tends to force lenses to hunt front to back and then lock on focus.

AF-C does not track during exposure. It can barely keep up during pre-exposure. I find continually half pressing the shutter release in AF-S to be much faster and more reliable. YMMV.

09-03-2010, 08:12 PM   #8
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QuoteOriginally posted by SOldBear Quote
Note that in LV, you need to hold down AF button to activate autofocus.
With the last update you now can focus in LV with the shutter button also.

09-03-2010, 08:50 PM   #9
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QuoteOriginally posted by ully Quote
With the last update you now can focus in LV with the shutter button also.
Not on the K20d (unless they added that feature in v1.04), which is what RML has. Only on the K7.

09-03-2010, 09:02 PM   #10
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Just remember that continual autofocus and exposure bracketing together isn't a good idea.
09-04-2010, 01:53 AM   #11
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QuoteQuote:
I assume the latter, but....
Im with you there M.L. but my but is different...

When Ive used AF-C, mostly with DA55-300 and longer K's and M's in conjunction
with 1.7xAF, after first shot (usally) on flying bird, DA seems to hunt a little more than
than other rig (1.7xAF+ K's,M's), in looking for that second shot.
Dont quite understand that
09-04-2010, 03:48 AM   #12
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QuoteOriginally posted by JeffJS Quote
If I remember correctly live view is activated with the preview option on the power switch on the K20d. The K7 has it's own button for live view but many other buttoned options have disappeared or been inappropriately placed (for those of us use to the layout of the 10/20).

LV on the K20 is pretty useless, especially for AF. I'm not too jazzed about the AF on the K7 live view either. It tends to force lenses to hunt front to back and then lock on focus.

AF-C does not track during exposure. It can barely keep up during pre-exposure. I find continually half pressing the shutter release in AF-S to be much faster and more reliable. YMMV.

I like the live view on the K7, but I use the standard autofocus that flips the mirror down for a second, focuses and then flips it back up. It is a lot faster.

As others have said, no auto focus during the exposure.
09-04-2010, 08:21 AM   #13
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Is lens data available since I guess "FA" series just exposure data or would it be worth
enabling in firmware, as part of a possible solution?
09-04-2010, 08:40 AM   #14
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Well, it was enough to get some shots, anyway. I've yet to load them up on a monitor, but there's some interesting stuff, there. (I ended up trying this old add on Vivitar close-up lens +10 on my FA 50: it made kind of a dreamy-effect in the OOF areas when I shot from an angle: we'll see if I actually got anything actually in the narrow DOF. Even with the LV, I was leaning way off balance to get there. Looks cool, though. )

Oh, and at some point, I did go to manual focus, at least for a few of them.
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