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04-13-2010, 03:12 AM   #1
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k-x focus-trap: very slow

I sometime find that focus-trap on k-x is really slow, even if the subject is in focus, it takes some time to trigger the shutter (and sometime even does not trigger).

Anyone having similar experience ? Any hints will be really appreciated.

04-13-2010, 03:56 AM   #2
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QuoteOriginally posted by yusuf Quote
I sometime find that focus-trap on k-x is really slow, even if the subject is in focus, it takes some time to trigger the shutter (and sometime even does not trigger).

Anyone having similar experience ? Any hints will be really appreciated.
Try it from a tripod, because this is, IMO, the target, when you put the camera to catch some birds or other critters, in good light. In low light almost every time I have used catch-in-focus the pics were OOF.
04-13-2010, 04:03 AM   #3
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I use it all the time in low light with manual lenses and it works perfectly.
04-13-2010, 05:15 AM   #4
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I don't think tripod is a solution. Even in perfect day light it's slow.

04-13-2010, 06:40 AM   #5
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Highly depends on the aperture that the lens attached is using, what are you using?
04-13-2010, 07:28 AM   #6
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QuoteOriginally posted by Eruditass Quote
Highly depends on the aperture that the lens attached is using, what are you using?
It's 2.8 however I would wonder if that's the case. My FA50mm autofocus fine at 1.4 and camera uses the same electronics for catch-in focus except that focusing mechanism is manual now.
04-13-2010, 07:38 AM   #7
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2.8 should be more than ok, perhaps it could be the subjects you are trying to focus on (low contrast? small in area?)
04-13-2010, 08:01 AM   #8
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happens to me as well all the time, with smc a 50/f2.0 is painfully slow, with kit lens it actualy fires anytime i hit shutter, even if it's at widest and mile out of focus...and yes, i have MF i allway thought it's user's fault, but now...

04-13-2010, 11:00 AM   #9
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Catch-in focus only works when the MF/AF switch is at AF position. So it doesn't really work with the kit lens.

QuoteOriginally posted by Bulldogface Quote
happens to me as well all the time, with smc a 50/f2.0 is painfully slow, with kit lens it actualy fires anytime i hit shutter, even if it's at widest and mile out of focus...and yes, i have MF i allway thought it's user's fault, but now...
04-14-2010, 04:59 AM   #10
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so if i'm gettin it right, catch-in is ruled out with any af lens?
04-16-2010, 05:26 PM   #11
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pentax is not very good at focus. try the single focus it is faster.
04-16-2010, 05:38 PM   #12
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QuoteOriginally posted by Bulldogface Quote
so if i'm gettin it right, catch-in is ruled out with any af lens?
Yep, unless you do the foil trick or pester Pentax to enable it (see K-x firmware request thread)
04-16-2010, 05:50 PM   #13
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fwiw... as a rank amateur.... i've been using my k-x with a few 'a' manual lenses.... and focus exclusively with 'catch in focus', aka focus trap..... i've had pretty good success, the pic shown is with my sigma 400mm apo 'a' f5.6 lens recently purchased.....
Camera: Pentax K-x
Exposure: 0.001 sec (1/1600)
Aperture: f/13.0
Focal Length: 400 mm
ISO Speed: 1600
Exposure Bias: -0.3 EV
04-16-2010, 07:19 PM   #14
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Sounds like something is wrong to me. I use the SMC Pentax-K 300mm f/4 on the Pentax K-x White on dog sled race, portraits (no speed needed) and snowmobile racing, and it hasn't failed me yet due to high speed subjects.
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