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05-11-2015, 02:33 PM   #1
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K-3 asks me to input focal length?

My K-3 has suddenly started asking me for the focal length of the lens on startup and shows F-- through the viewfinder, even with fully automatic lenses. I've tried both the 21mm and the 18-55mm, and I have the same problem with both, so I'm guessing this is a problem with the camera body. What do you think the problem is? Do I need to try cleaning one of the contacts, and, if so, which one, and how do I do it?

05-11-2015, 02:36 PM   #2
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As you say if it happens on multiple lenses it is likely the body.
Definitely try cleaning the contacts first. Hopefully that eliminates needs to send it in for repair.
Clean them all. Can't hurt to do more than necessary. :-)

I just use my fingers.:-) But lens cleaning or sensor cleaning fluid should work with a q-tip or even better, a lintless cleaning cloth.
05-11-2015, 02:43 PM   #3
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OK, cool. Do I need to do anything special to keep dust from getting onto the sensor while the lens is off the body?

---------- Post added 05-11-15 at 05:57 PM ----------

Update: Tried cleaning the contacts on both the body and the lens (21mm) with a microfiber cloth and no cleaning fluid, and still have the same problem.
05-11-2015, 03:20 PM   #4
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You could try resetting the camera to default settings.

05-11-2015, 03:58 PM   #5
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Tried cleaning contacts with isopropyl alcohol, same problem.

Tried resetting camera to default settings, same problem.
05-11-2015, 05:16 PM   #6
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could the af.s, af.c, m switch have anything to do with this?
05-11-2015, 06:20 PM   #7
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AFAIK the only thing that will cause "F _ _ " is the camera not seeing a lens. Which is a communication failure which means a contact problem.

Look at the contacts on the camera and make sure all sticking up as they should. There are 7 and six should be proud, third from the left (facing) should be flatter and not as proud.
05-11-2015, 06:29 PM   #8
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Checked the prongs, and compared them against my dad's K-5 II, and everything looks fine-- no obvious problems there.

Also tried leaving the battery out of the camera for 15 minutes or so to give any capacitors time to fully bleed off, and that didn't help.

05-11-2015, 06:33 PM   #9
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Sounds like something is wrong with the body contacts then.
05-11-2015, 07:12 PM   #10
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Your lenses don't have aperture rings do they? If they do and the aperture rings aren't in "A", this will happen.
05-11-2015, 07:24 PM   #11
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ah yeh the 'using the aperture ring' on permitted '2' in custom settings.....
05-11-2015, 07:32 PM   #12
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QuoteOriginally posted by Outis Quote
Also tried leaving the battery out of the camera for 15 minutes or so to give any capacitors time to fully bleed off, and that didn't help.
Did you hold down the shutter with the battery out? When I shot with a Sony DSLR the common practice was to remove battery and hold shutter for 30 seconds and it would drain the internal reserve battery completely.
05-11-2015, 07:42 PM   #13
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QuoteOriginally posted by K David Quote
Your lenses don't have aperture rings do they? If they do and the aperture rings aren't in "A", this will happen.
Tried it on lenses both with and without aperture rings, with the same result :-( But good thought.
05-11-2015, 08:23 PM   #14
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Sure when mounting the lenses they can be turned to the correct end position?

Even missing the point where the contacts should meet by 0.3mm could prevent communication.

EDIT:
One possible cause of such behaviour can be a damaged aperture actuator in the body. Which itself can be caused by a damaged aperture actuator at one of your lenses.
05-11-2015, 08:25 PM   #15
mee
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..is the camera still under warranty?
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