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Old Jun 9, 2007, 12:59 AM   #21
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fusion1420 wrote:
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Is there any way to get this to work with a DL? I could have sworn there was a setting to turn off the shutter actuation until the object is in focus, but I can't get it to work with my M42 takumar.

TIA!
Not sure on the isT's but on the K's it is default if you leave it in AF mode with a MF lens... limitation being it is center point AF confirmation/trigger only.

You also need to be pretty slow in your focus adjustment or you may have overshot the focus (if a close range/shallow DOF shot) by the time the shutter trips.



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Old Jun 9, 2007, 2:22 AM   #22
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Thanks, Darren and Tom for your replies. Cheers.
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Old Jun 9, 2007, 4:56 AM   #23
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fusion1420 wrote:
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Is there any way to get this to work with a DL? I could have sworn there was a setting to turn off the shutter actuation until the object is in focus, but I can't get it to work with my M42 takumar.

TIA!
I found that some lenses worked with this method and some didn't. No particular scientific test, but set the camera up the same and use 2 different makes of lens, and on one the focus trap works and on the other it doesn't.

Darren

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Old Jun 10, 2007, 1:58 AM   #24
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Dal1970 wrote:
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fusion1420 wrote:
Quote:
Is there any way to get this to work with a DL? I could have sworn there was a setting to turn off the shutter actuation until the object is in focus, but I can't get it to work with my M42 takumar.

TIA!
I found that some lenses worked with this method and some didn't. No particular scientific test, but set the camera up the same and use 2 different makes of lens, and on one the focus trap works and on the other it doesn't.

Darren
Perhaps it depends on how sharp the lens is wide open. If the lens is too soft, the camera might never see enough contrast to detect focus. In particular, if an m42 lens is being used with an adapter that doesn't allow focusing to infinity, that would prevent the technique from working at longer range.

I've personally tried it on my Pentax A 50mm, Takumar 135mm f/2.5, Sears 80-200mm, an old Tamron 28mm f/2.8, and with the 135mm stacked on a 2x TC and it worked for all those. I haven't noticed if any were more sluggish to snap shots or any other problems, but the A 50mm definitely produced the sharpest photos.

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Old Jun 10, 2007, 6:34 AM   #25
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That could well be a deciding factor when using this technique. As I said, no scientific test, but in fairness a couple of the lenses were cheap rubbish.


Darren

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Old Jun 13, 2007, 12:20 AM   #26
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I'll have to try it out with some other manual lenses and report back. I haven't yet found a way to stop the shutter from firing when I initially press the button, regardless of focus.
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Old Jun 13, 2007, 2:41 AM   #27
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fusion1420 wrote:
Quote:
Is there any way to get this to work with a DL? I could have sworn there was a setting to turn off the shutter actuation until the object is in focus, but I can't get it to work with my M42 takumar.

TIA!
Hi Fusion1420,

Focus trap is not dependent on Pentax DSLR model, so the DL is not the problem.

Here's a link to another forum where Ron Brandon (brandx) is the focus trap guru. There are links to all the tricks to make it work with different lenses, and there is a link in the first thread linked to that explains his method of using this feature.

http://forums.dpreview.com/forums/re...ssage=23560715

Apparently, you have to short out the pins on the lens mount of the camera body with aluminum foil for M42 lenses. This will fool the camera into thinking that there is a Pre-A bayonet mount lens attached, and will prevent the camera from firing until focus confirmation is made.

You can also make it work with AF lenses by insulating some of the pins from contacting the matching pins on the lens with some scotch tape.

Scott
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Old Jun 13, 2007, 11:20 PM   #28
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Snostorm - You're the man! That did it. Quite hack-jobish, but effective nonetheless.

Thanks so much.

Scott
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Old Jun 14, 2007, 12:21 AM   #29
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i did notice in my ds book a menu option for focusing using screw mount lenses

not sure if that will make a difference


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Old Jun 14, 2007, 5:07 AM   #30
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Gumnut wrote:
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i did notice in my ds book a menu option for focusing using screw mount lenses

not sure if that will make a difference

Actually even the K10D manual doesn't really make mention of it either... just a experiencially learned side effect of leaving the camera in AF with a MF lens.

OOPS just rechecked and actually it does of the indicator confirmation, but no mention of the "trap" function.

And actually on the K10D you get the AF confirmation in AF or MF... but the shutter inhibit/trigger "trap" happens only if left in AF, which again they do not mention.
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