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12-13-2009, 04:33 PM   #1
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K-x with prime -- no aperture control

Hi all,

I've just recently got a SMC-M 50mm f2 and I was trying to figure out how to use it with the K-x. I followed everyone's example online: enable Using Aperture Ring, use Av mode (or Manual), use Manual Focus, focus, press AE-L to lock meter, then shoot. However, it seems that the pictures come out with the aperture wide open. Looking through the lens while mounted, no matter which aperture I set it to it remains wide open. Taken the lens off the camera, turning the aperture ring set the aperture correctly (I could see the diaphragm close up and open fine). There is a part on the K-x that move the aperture dial up and down to open and close aperture on the automatic lenses. That part seems to be pretty rigid and does not move. Remounted my kit lens and it works fine on all modes.

Why is the aperture won't change when mounted? What am I doing wrong?

12-13-2009, 04:49 PM   #2
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note that in Av mode, the camera only shoots wide open

use manual mode, meter with green button (or equivelent function) and shoot.
12-13-2009, 04:49 PM   #3
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The lens won't stop down while you're looking through it- only once you take the picture. Are you sure it isn't stopping down? Try to set it to F22, 1sec shutter, and point the camera at yourself. You'll be able to tell if it was stopped down or not!

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12-13-2009, 04:50 PM   #4
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This is what you need to do...

1 - set "Using Aperture Ring" to "Permitted"
2 - set "Action in M mode" of the Green Button to "Tv Shift"
3 - set your camera to manual "M"
4 - set the desired aperture setting on your lens manually
5 - compose your shot and press the Green Button to set the shutter speed (pressing the exposure compensation button seems to do the same thing)
6 - shoot

12-13-2009, 05:12 PM   #5
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Adam and Nameles,

That was it. The combination of me misusing the buttons in different mode caused the problem. When I was in the M mode, I was using the AE-L. When I was in Av mode, I was playing with the Green button.

Thanks all.
12-14-2009, 05:29 AM   #6
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Good that a solution emerged.

Now post some pix taken with your manual lens!
12-14-2009, 07:18 AM   #7
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QuoteOriginally posted by rawr Quote
Good that a solution emerged.

Now post some pix taken with your manual lens!
Will do. However, the lens seems to have some crazy amount of haze that affects metering. I took it apart to clean it (one of the glasses inside was quite dirty -- like gunk dirty, like Bangkok prostitute dirty) and it seems a bit better but the haze is still there if look carefully enough. I think it might be sitting in between the last piece of glass that I was unable to open. Anyway, it seems that the picture is unaffected, and it was able to take pic at f2, iso400 @ 1/300 and came out looking clean but not bright. I'll post something once I got a chance after work.
12-14-2009, 08:16 AM   #8
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QuoteOriginally posted by Nameles Quote
This is what you need to do...

1 - set "Using Aperture Ring" to "Permitted"
2 - set "Action in M mode" of the Green Button to "Tv Shift"
3 - set your camera to manual "M"
4 - set the desired aperture setting on your lens manually
5 - compose your shot and press the Green Button to set the shutter speed (pressing the exposure compensation button seems to do the same thing)
6 - shoot
Not to hijack the thread but I posted a question in beginners corner but, am too inpatient to wait for a rely.

but, I did just that with a super-tak with adapter to k-x. I can not get the green button nor exp comp to meter correctly. they both want to default to 1.6"

also, when putting on the super-tak, the camera does not ask me to set focal length every time. How do you do it manually if the camera didn't ask?

thanks

12-14-2009, 09:35 AM   #9
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QuoteOriginally posted by slow2focus Quote
Not to hijack the thread but I posted a question in beginners corner but, am too inpatient to wait for a rely.

but, I did just that with a super-tak with adapter to k-x. I can not get the green button nor exp comp to meter correctly. they both want to default to 1.6"
I saw similar issue on my but only at higher fstop. When I set to f8, it sets the shutter to 0.8". When I set to f22, it sets the shutter to 0.8" as well. Not sure why yet but I didn't want to voice it till I had more time to check it out.


QuoteQuote:
also, when putting on the super-tak, the camera does not ask me to set focal length every time. How do you do it manually if the camera didn't ask?

thanks
There is an option in the menu. I think it's under the 2nd or 3rd tab, all the way at the bottom, there is an option "Set Focal Length" Try that to see if you can see it.
12-15-2009, 07:37 PM   #10
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iso 400, f2, shutter 1/13 .... Belgium beer

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