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02-13-2008, 07:17 AM   #1
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Question about using manual focus lens.

I'll give this another shot.

I've recently acquired an SMC A 28mm f/2.8 which I'm using on a K110D. With the aperture ring set to "A" and the camera set in aperture mode, the widest aperture setting I can get is f/4. Is there some known reason as to why I wouldn't be able to open the lens to f/2.8 while in Av mode, or is the lens malfunctioning?

Thanks.

-XM

02-13-2008, 07:34 AM   #2
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you should check the contacts on the back of the lens, for any dirt. they can be cleaned with a non abrasive pencil eraser.

the contacts on your lens code the maximum and minimum apature of the lens any dirt, or faulty contact can cause incorrect apature reading.

you can also check the camera body for similar contaminated contacts but be VERY careful, if you attempt to clean them that you do not get anything in the mirror box, that can eventually make it to the sensor.
02-13-2008, 07:54 AM   #3
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Original Poster
QuoteOriginally posted by Lowell Goudge Quote
you should check the contacts on the back of the lens, for any dirt. they can be cleaned with a non abrasive pencil eraser.

the contacts on your lens code the maximum and minimum apature of the lens any dirt, or faulty contact can cause incorrect apature reading.

you can also check the camera body for similar contaminated contacts but be VERY careful, if you attempt to clean them that you do not get anything in the mirror box, that can eventually make it to the sensor.
Lowell Goudge:

Following your advice, I wiped away a slight smudge from one of the contact points on the lens. Damned if that didn't fix the problem.

Thank you. I'm in your debt.

Do you accept checks? Visa?

-XM
02-13-2008, 08:23 AM   #4
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QuoteOriginally posted by XMACHINA Quote
Lowell Goudge:

Following your advice, I wiped away a slight smudge from one of the contact points on the lens. Damned if that didn't fix the problem.

Thank you. I'm in your debt.

Do you accept checks? Visa?

-XM
Actually neither, a simple package received by mail of an 85mmF1.8 lens would suffice.

Just joking obviously, but I am looking for one

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