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Old Aug 28, 2008, 12:39 PM   #1
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Hi all, need some help

Just got hold of an old200mm RMC Tokina f3.5 p/k mount lens at a garage sale.

It fits fine onto my K100D s but seems to be stuck at the widest apperture (3.5).

With the lens off the camera the apperture works fine. Via the ring or the little lever.

Lens does not have a M / A slide or setting like some of my M42 lenses. Seems that the little lever that contols the apperture get pushed to wide open once the lens click into the camera.

Do I miss something simple (camera setting) or should I just clip/cut the lever off?

Any help will be great.

Cheers,

Alfred










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Old Aug 28, 2008, 2:00 PM   #2
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With a k-mount lens, ensure that allow aperture has been set in the custom menu.

The lens will always stay wide open to allow you to focus.

Just set the lens to the aperture you want, focus, and press either the green button or the AE-L button (not sure which one you have). This will briefly stop down the lens and set the exposure.

Takes a fraction of a second, and soon becomes a habit.



Dal
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Old Aug 29, 2008, 2:27 PM   #3
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Thx a million Dal,

thx to your advice I figured it out at last, on the K100d it seems that you have to be in M (not Av which I usually use with my M42's) and then press the shutter & AE-L to set the shutter speed.

Alfred


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Old Aug 30, 2008, 12:13 PM   #4
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Yes - that's how it works. I find it rather useful to use the Av mode when I'm going to be shooting with the lens wide open anyway, because the camera continuously meters. Otherwise, I don't mind pushing the button to meter at all.
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Old Sep 2, 2008, 2:31 AM   #5
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Great suggestion! My LBA brought me many eBay lenses lately, including some fine old Tokumars and other PK-mounts without M/A switches. I'd flagged some of those for resale because they wouldn't stop down on my K20D. Now I know the secret - goto M(anual) mode, focus, hit Green button to set exposure, then shoot.

Unfortunately, that doesn't work with screwmount lenses on a M42-PK adapter, if a lens has no M/A switch. The trick there, if I don't intend to resell the lens, is to superglue the lensmount's aperture peg down. A drop of glue, a plastic c-clamp, a couple hours wait to be sure, and the deed is done. I did that with one lens; haven't yet tried to remove the glue and undo the mod.

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Old Sep 2, 2008, 10:23 AM   #6
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RioRico wrote:
Quote:
Unfortunately, that doesn't work with screwmount lenses on a M42-PK adapter, if a lens has no M/A switch. The trick there, if I don't intend to resell the lens, is to superglue the lensmount's aperture peg down. A drop of glue, a plastic c-clamp, a couple hours wait to be sure, and the deed is done. I did that with one lens; haven't yet tried to remove the glue and undo the mod.
i've got an old soligar zoom that doesn't have the m/a button. i bent the pin a small amount and pushed it into the mount. now it works in Av just fine..

roy
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