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parsons · 02-20-2012, 11:49 AM

for some reason i am having trouble focusing my F-zoom 70-200 to infinity on my K-r. it has the problem especially at the 200 end.

It worked fine on my Ist*-D.

any ideas?

i was thinking of selling it and putting the money towards getting a FA 77.

Is there an easy fix for this sort of problem or is the lens/camera broken?

cheers for any responses

parsons · 02-20-2012, 11:50 AM

Pentax-F 70-200mm F4-5.6 Reviews - Non-SMC Pentax Zoom Lenses - Pentax Lens Reviews & Lens Database

its this one if this helps?

Adam · 02-20-2012, 01:15 PM

Try checking for FF/BF:

Fixing Front and Back Focus - Introduction - PentaxForums.com

parsons · 02-20-2012, 02:06 PM

does this move the sensor or something then? the lens wont manually focus to infinity.- even though on the focus markings it reads byond infinity.

Marc Sabatella · 02-20-2012, 08:47 PM

What problems are you seeing? Failing to focus, or just images not as sharp as you expect? Can you post samples? I'm guessing you are making the mistake of comapring against the istD at 100%, which is to say, you are blowing up the K-r image *much* larger. so no surprise it looks softer in comparison.

02-20-2012, 11:49 AM	#1
parsons Inactive Account Join Date: Apr 2010 Location: ENGLAND Posts: 389	focusing to infinity problems K-r for some reason i am having trouble focusing my F-zoom 70-200 to infinity on my K-r. it has the problem especially at the 200 end. It worked fine on my Ist*-D. any ideas? i was thinking of selling it and putting the money towards getting a FA 77. Is there an easy fix for this sort of problem or is the lens/camera broken? cheers for any responses

02-20-2012, 01:15 PM	#3
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,609	Try checking for FF/BF: Fixing Front and Back Focus - Introduction - PentaxForums.com 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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02-20-2012, 11:50 AM	#2
parsons Inactive Account Join Date: Apr 2010 Location: ENGLAND Posts: 389 Original Poster	Pentax-F 70-200mm F4-5.6 Reviews - Non-SMC Pentax Zoom Lenses - Pentax Lens Reviews & Lens Database its this one if this helps?

02-20-2012, 02:06 PM	#4
parsons Inactive Account Join Date: Apr 2010 Location: ENGLAND Posts: 389 Original Poster	does this move the sensor or something then? the lens wont manually focus to infinity.- even though on the focus markings it reads byond infinity.

02-20-2012, 08:47 PM	#5
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	What problems are you seeing? Failing to focus, or just images not as sharp as you expect? Can you post samples? I'm guessing you are making the mistake of comapring against the istD at 100%, which is to say, you are blowing up the K-r image much larger. so no surprise it looks softer in comparison.

focusing to infinity problems K-r

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