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12-05-2010, 12:58 PM   #1
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Sigma 400/5.6 non-APO - Questions.

I recently acquired this lens, a Sigma 400/5.6 non-APO and would like to know a couple of things about the camera settings.
I realize this is a "manual" lens (the camera is requesting focal length input) and I did go over (this happens to me all the time with such lenses) the Sticky Thread on using manual lenses, I am still perplexed.
Edit: Is this really a "manual" lens in the sense that there is an "A" setting on it???

1. The camera is set at M (manual) mode. K20D or K7.
2. The proper focal length is input.

Each picture taken shows that it is at f 5.6, no matter what I try.

Is there any way that this lens can be stopped down?

Thanks in advance for any tips.

JP


Last edited by jpzk; 12-05-2010 at 03:09 PM.
12-05-2010, 01:59 PM   #2
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Could be a few things.
Have you set your camera to allow for apature ring?
Does the lens have an "A" on the ring?
Have you tried it in AV mode?
Are you sure it is locking into place so all contacts are made when mounting?
12-05-2010, 03:01 PM   #3
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QuoteOriginally posted by Ron Kruger Quote
Could be a few things.
Have you set your camera to allow for apature ring?
Yes, did that, as I mentioned above.
Does the lens have an "A" on the ring?
Yes it does.
Have you tried it in AV mode?
Yes, I tried that too.
Are you sure it is locking into place so all contacts are made when mounting?
I re-mounted the lens three times to make sure it was locking in properly.
I did try with the lens in the "A" position, then with the aperture ring f-stops ... still having the F5.6 result.

Thanks for the reply, Ron.

Last edited by jpzk; 12-05-2010 at 03:57 PM.
12-05-2010, 05:04 PM   #4
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Then, it may be a problem with the contacts. Try cleaning them and check if any are missing.

12-05-2010, 05:08 PM   #5
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QuoteOriginally posted by Ron Kruger Quote
Then, it may be a problem with the contacts. Try cleaning them and check if any are missing.
Alright, I'll try cleaning, re-mounting again and see what happens.
Thanks!

JP
12-05-2010, 05:57 PM   #6
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Hi Jp, might want to check (K20) custom menu #26,green button and ensure that
shift works for your app. good to have optical preview enabled too.
Still have to green button for A contacts also, you should have F number display
in viewfinder with ring at "A", goes blank when you shift ring manually,so you
might want to check that front/back E-dials are configured right.
should be able to confirm by pointing at bright light, green button, then engage
optical preview and see iris stop down and viewfinder darken.
12-07-2010, 07:21 PM   #7
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All is well now, working as it should.
Thanks for the help, people!

JP
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