80-320mm won't focus to infinity

**akptc** · 10-10-2012, 10:47 PM

Got this one recently here on this site, the lens looks near new and works great to about 135mm FL but anything past that it just won't focus in AF mode. I tried focusing to infinity manually but the image comes out blurry. I'd hate to throw it away, does anyone know if this is an easy fix? I am using it on the K-5. The camera works fine with all my other lenses.

I'd appreciate any and all help on this as I really like this lens.

Last edited by akptc; 10-10-2012 at 11:40 PM.

**akptc** · 10-10-2012, 11:40 PM

Here is a shot taken at 320mm

Na Horuk · 10-11-2012, 12:20 AM

When you focus manually, how does the focus ring turn?

**akptc** · 10-11-2012, 08:53 AM

The manual focus ring turns OK, w/out obstructions, if that's what you meant?

**akptc** · 12-14-2012, 08:41 AM

False alarm, it works fine, it was a combination of poor lighting and my focusing technique. All is good now; actually, the is now my very favorite zoom lens - cheap enough not to worry about damage and I love the IQ.

**LaurenOE** · 12-14-2012, 08:46 AM

The 80-320 is an easy lens to take apart, and if not put back together correctly, will have a bit of trouble to focus to infinity. How do I know? Been there done that. There are some little screws/clamps that hold the outer lens assembly in "just-a-position" of adjustment. If someone put the lens back together the wrong way (or over time) you might get that.

Of course in the post that just appeared it could also be user error.

10-10-2012, 10:47 PM	#1
akptc Site Supporter Join Date: Feb 2008 Location: USA Photos: Gallery Posts: 771	80-320mm won't focus to infinity Got this one recently here on this site, the lens looks near new and works great to about 135mm FL but anything past that it just won't focus in AF mode. I tried focusing to infinity manually but the image comes out blurry. I'd hate to throw it away, does anyone know if this is an easy fix? I am using it on the K-5. The camera works fine with all my other lenses. I'd appreciate any and all help on this as I really like this lens. Last edited by akptc; 10-10-2012 at 11:40 PM.

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10-10-2012, 11:40 PM	#2
akptc Site Supporter Join Date: Feb 2008 Location: USA Photos: Gallery Posts: 771 Original Poster	Here is a shot taken at 320mm

10-11-2012, 12:20 AM	#3
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	When you focus manually, how does the focus ring turn?

10-11-2012, 08:53 AM	#4
akptc Site Supporter Join Date: Feb 2008 Location: USA Photos: Gallery Posts: 771 Original Poster	The manual focus ring turns OK, w/out obstructions, if that's what you meant?

12-14-2012, 08:41 AM	#5
akptc Site Supporter Join Date: Feb 2008 Location: USA Photos: Gallery Posts: 771 Original Poster	False alarm, it works fine, it was a combination of poor lighting and my focusing technique. All is good now; actually, the is now my very favorite zoom lens - cheap enough not to worry about damage and I love the IQ.

12-14-2012, 08:46 AM	#6
LaurenOE Site Supporter Join Date: Sep 2009 Location: Back in Florida, but worldwide gigs! Photos: Albums Posts: 3,690	The 80-320 is an easy lens to take apart, and if not put back together correctly, will have a bit of trouble to focus to infinity. How do I know? Been there done that. There are some little screws/clamps that hold the outer lens assembly in "just-a-position" of adjustment. If someone put the lens back together the wrong way (or over time) you might get that. Of course in the post that just appeared it could also be user error.