lens suddenly has focusing issues

kjfaust · 05-08-2011, 02:33 PM

hi guys,

one of my lens, tamron 28-75, suddenly has focusing issues

I've been using it for a while now with no problem but a few weeks ago when I was going to use it, I've noticed that it won't focus properly, like a front/back focus issue (don't know which

)

I'll post some pictures later

but any suggestions on what I can do to fix it? or where I can send to get it fixed?
I'm not the original owner of the lens and I know that its a few years old now.

Thanks!

Marc Sabatella · 05-08-2011, 05:08 PM

The chances that it suddenly developed a focus issue other than complete failure to focus at all (that could happen) is practically zero. So I'd focus on understanding what is actually going on; and posting pictures should help.

There are any number of things that can legitimate cause a camera & lens to focus somewhere other than you actually intended - for example, something else within range of the chosen focus sensor happening to grab the systems attention instead of the thing you want. But if there was an actual camera defect (much more likely than a lens defect) that caused the system to focus incorrectly, it would have been there from the beginning. I guess maybe dropping the camera hard might knock the AF sensor out of alignment.

kjfaust · 05-08-2011, 05:23 PM

sorry, I'll take some pictures when I get home later tonight

I've only noticed the problem with the tammy, even on manual focus it's doing the same thing.
my kit lens focuses well and so is my M 50mm 1.7

don't know what the actual problem with the lens is, hopefully I can still get it fixed

because its my fave lens

bobmaxja · 05-08-2011, 05:27 PM

Not focusing on manual !!! Hum

yusuf · 05-09-2011, 07:27 AM

Any possibilities of physical impact resulting in misalignment?

jane7l · 05-09-2011, 01:27 PM

ciao

a had an issue with tamron 17-50. suddenly did not focus correct, but really wrong, not just a margin. and it was just out of warranty. after inspection in in a service center got focus electronics issue reported. replacement cost me 50eur, works fine since

good luck

05-08-2011, 02:33 PM	#1
kjfaust Senior Member Join Date: Apr 2008 Location: maryland Posts: 104	lens suddenly has focusing issues hi guys, one of my lens, tamron 28-75, suddenly has focusing issues I've been using it for a while now with no problem but a few weeks ago when I was going to use it, I've noticed that it won't focus properly, like a front/back focus issue (don't know which ) I'll post some pictures later but any suggestions on what I can do to fix it? or where I can send to get it fixed? I'm not the original owner of the lens and I know that its a few years old now. Thanks!

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05-08-2011, 05:08 PM	#2
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	The chances that it suddenly developed a focus issue other than complete failure to focus at all (that could happen) is practically zero. So I'd focus on understanding what is actually going on; and posting pictures should help. There are any number of things that can legitimate cause a camera & lens to focus somewhere other than you actually intended - for example, something else within range of the chosen focus sensor happening to grab the systems attention instead of the thing you want. But if there was an actual camera defect (much more likely than a lens defect) that caused the system to focus incorrectly, it would have been there from the beginning. I guess maybe dropping the camera hard might knock the AF sensor out of alignment.

05-08-2011, 05:23 PM	#3
kjfaust Senior Member Join Date: Apr 2008 Location: maryland Posts: 104 Original Poster	sorry, I'll take some pictures when I get home later tonight I've only noticed the problem with the tammy, even on manual focus it's doing the same thing. my kit lens focuses well and so is my M 50mm 1.7 don't know what the actual problem with the lens is, hopefully I can still get it fixed because its my fave lens

05-08-2011, 05:27 PM	#4
bobmaxja Veteran Member Join Date: Mar 2010 Location: Laval, Quebec Canada Posts: 2,171	Not focusing on manual !!! Hum

05-09-2011, 07:27 AM	#5
yusuf Pentaxian Join Date: Nov 2008 Location: Palo Alto, CA Photos: Gallery Posts: 2,497	Any possibilities of physical impact resulting in misalignment?

05-09-2011, 01:27 PM	#6
jane7l Forum Member Join Date: Jun 2010 Location: slovenia Posts: 57	ciao a had an issue with tamron 17-50. suddenly did not focus correct, but really wrong, not just a margin. and it was just out of warranty. after inspection in in a service center got focus electronics issue reported. replacement cost me 50eur, works fine since good luck