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08-30-2011, 02:44 PM   #1
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FA 28-70/f4. Problem to detect lens identity on K-5.

Just got the FA 28-70/f4 in the mailbox. Bargain on ebay, I thought....
On my K-5 it seems to be a K or M lens if I look att the exif.

However, it autofokus sometimes but it always says MF on the lcd. One strange thing is also that the lcd shows an aperturevalue, while the top-screen just show F--, as in the viewfinder. I can change the value on the lcd with the thumbscrew, but in Av-mode it dont give right exposure.
I have cleaned the contacts, the lens and the apertureblades look really good. K-5 is ok with my other lenses.
Whats the problem? Bad contact inside the the lens? Broken chip?
Easy to fix?

08-30-2011, 03:22 PM   #2
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Sounds like it might be defective. Is the aperture ring in the A position?

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08-30-2011, 03:43 PM   #3
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Location: Falun
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Original Poster
Yes it is in A. I moved the aprturering back and forth. And defective in som way, yes.
Intresting though why there is different info on the both screens. Is one the cameras signal to the lens and the other the feedback from the lens, ackording the aperture?

I saw some nice pictures here:

Lots of parts, but this must be something "electrical"?
What do you think?

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