Sigma 17-70 lens problem on K-5

NogBoy13 · 02-10-2013, 07:26 PM

I have a Sigma 17-70 on my K-5. I have noticed that I cannot access F2.8 in camera anymore. I cant get the lens to open wider than F4 in any mode.
Everything on the lens seems to be hunky dory with no sticky blades or anything. Why is this? Could it have been the new 1.14 firmware install? Any
feedback appreciated.

Adam · 02-10-2013, 07:34 PM

It could be that the lens is transmitting the wrong focal length info- try cleaning the contacts! Also, I hate to state the obviously, but you know that F2.8 is only available at 17mm, right?

**kiwi_jono** · 02-10-2013, 09:14 PM

For what its worth, I've got fw1.14 and a Siggy 17-70 and f2.8 works fine.

As Adam says it could be cause by a dirty contact potentially.

NogBoy13 · 02-12-2013, 10:35 PM

Thanks for feedback. But yep... I know 2.8 is only accessible at the wide end. I have tried cleaning contacts on everything... camera and
lens. All other lenses work fine on the K-5 and the 17-70 is similarly dysfunctional on my K-20. Beats me. Just cant access F2.8 no matter what.

02-10-2013, 07:26 PM	#1
NogBoy13 Junior Member Join Date: Jul 2011 Location: Bunbury Posts: 29	Sigma 17-70 lens problem on K-5 I have a Sigma 17-70 on my K-5. I have noticed that I cannot access F2.8 in camera anymore. I cant get the lens to open wider than F4 in any mode. Everything on the lens seems to be hunky dory with no sticky blades or anything. Why is this? Could it have been the new 1.14 firmware install? Any feedback appreciated.

02-10-2013, 07:34 PM	#2
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,595	It could be that the lens is transmitting the wrong focal length info- try cleaning the contacts! Also, I hate to state the obviously, but you know that F2.8 is only available at 17mm, right? Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

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02-10-2013, 09:14 PM	#3
kiwi_jono Loyal Site Supporter Join Date: Dec 2009 Location: Christchurch, New Zealand Photos: Gallery \| Albums Posts: 2,437	For what its worth, I've got fw1.14 and a Siggy 17-70 and f2.8 works fine. As Adam says it could be cause by a dirty contact potentially.

02-12-2013, 10:35 PM	#4
NogBoy13 Junior Member Join Date: Jul 2011 Location: Bunbury Posts: 29 Original Poster	Thanks for feedback. But yep... I know 2.8 is only accessible at the wide end. I have tried cleaning contacts on everything... camera and lens. All other lenses work fine on the K-5 and the 17-70 is similarly dysfunctional on my K-20. Beats me. Just cant access F2.8 no matter what.