Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-30-2013, 10:24 AM   #1
Veteran Member




Join Date: Jan 2007
Location: New Mexico
Photos: Albums
Posts: 1,125
K-5II focusing accuracy

If there is one complaint that I have regarding my K-5, it is its erratic autofocusing, and I'm not referring to focusing speed. I'm referring to the fact that its focusing is not always precise. Is the K-5II significantly more accurate and consistent in its AF?

Thanks,
Rob

08-30-2013, 10:53 AM   #2
Senior Member
Action Jackson's Avatar

Join Date: Jun 2011
Location: Markham, Ontario, CANADA
Posts: 243
Does it do this for all your autofocus lenses? and under what conditions are you trying to focus in?
08-30-2013, 10:58 AM   #3
Site Supporter




Join Date: Jul 2011
Location: Auckland, New Zealand.
Posts: 328
QuoteOriginally posted by robgo2 Quote
K-5II focusing accuracy
If there is one complaint that I have regarding my K-5, it is its erratic autofocusing, and I'm not referring to focusing speed. I'm referring to the fact that its focusing is not always precise. Is the K-5II significantly more accurate and consistent in its AF?

Thanks,
Rob
Hi Rob,
A few questions-
Does the K-5 have this fault in low light only or is it all the time? Also is it happening with a variety of lenses or one in particular?

The K-5ii /s does focus better in low light then the K-5 and I noticed a substantial focusing improvement with my K-5iis across all my lenses.(I also found the lack of AA filter on the K-5iis sensor made me realise how good some of my lenses are

May I suggest that you do a test with a large focusing target using the central focusing point. Do the tests in good light, at various focus distances, starting from the the ends of the focal range of the lens each time.
Repeat the tests with other lenses and this should give you an idea whether it is the camera or the lens that is at fault.

Hope this helps
Chris
08-30-2013, 11:17 AM   #4
Veteran Member




Join Date: Jan 2007
Location: New Mexico
Photos: Albums
Posts: 1,125
Original Poster
QuoteOriginally posted by ak_kiwi Quote
Hi Rob,
A few questions-
Does the K-5 have this fault in low light only or is it all the time? Also is it happening with a variety of lenses or one in particular?

The K-5ii /s does focus better in low light then the K-5 and I noticed a substantial focusing improvement with my K-5iis across all my lenses.(I also found the lack of AA filter on the K-5iis sensor made me realise how good some of my lenses are

May I suggest that you do a test with a large focusing target using the central focusing point. Do the tests in good light, at various focus distances, starting from the the ends of the focal range of the lens each time.
Repeat the tests with other lenses and this should give you an idea whether it is the camera or the lens that is at fault.

Hope this helps
Chris
I have found my K-5 to be somewhat inconsistent in all levels of light, but especially in low light.

Rob

08-30-2013, 11:22 AM   #5
Administrator
Site Webmaster
Adam's Avatar

Join Date: Sep 2006
Location: Arizona
Photos: Gallery | Albums
Posts: 41,422
QuoteOriginally posted by robgo2 Quote
I have found my K-5 to be somewhat inconsistent in all levels of light, but especially in low light.

Rob
When the specs say -1EV, you can expect the AF to be hit and miss in the -1 to 1 EV range and quite reliable when there's more light. The K-5 II's spec goes down to -3 EV, so you can expect it to be hit and miss between -3 and -1 EV, but above that (i.e. in thee K-5's specified operating range), it should be noticeably more reliable. As you'll read in our review, low light decisiveness is the main improvement that the K-5 II's AF system brings to the table.

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)



PentaxForums.com's high server and development costs are user-supported. You can help cover those costs by donating. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

08-30-2013, 01:28 PM   #6
Veteran Member




Join Date: Jul 2009
Location: Mount Joy, PA
Photos: Gallery | Albums
Posts: 529
My K-5 auto focus was initially fine, as best as I can tell, but after having the camera for a few months it started behaving very strangely. CRIS spent more time with the camera than I did using it, but they never determined what the problem was. Eventually, Pentax replaced the body with a K-5 II, as the original was out of production by that time.

Even in good light (bright sun, contrasty scenes) the camera could not reliably judge distance of the same subject. I would auto-focus on a subject, say a tree or large street sign - usually at or near "infinity" distances, and each time the focus point according to the distance scale on the lens would be different. We're talking severe front and back focus issues of the same subject/scene over a dozen test shots. At first I was convinced my Tamron 17-50mm was the culprit, and that lens went to service several times, but Tamron insisted there was nothing wrong with the lens. They even calibrated the lens to the body, but that didn't seem to do it.

Then the body started doing the same weird focusing with both a Pentax DA L 55-300mm and my DA* 50-135mm. Both lenses had already been to CRIS to address focusing issues and they performed brilliantly when I first got the K-5. Then I tried an 18-55mm kit lens, a DA 35mm 2.4, and a Sigma macro - same focus problems. I became convinced the camera needed servicing. As I said, CRIS worked on the camera several times, but each time it came back it demonstrated the same problems. It's a long and sordid tale, but in the end the original K-5 went off to live at Pentax. While I doubt Pentax will perform an autopsy, I certainly hope they take some time to seriously consider the problem. I spent a fortune on shipping sending equipment all over the country!

Like I said, the K-5 was fine at first. Terrific, actually. It did everything much better than the K-7 that preceded it. When it started showing problems, CRIS even disassembled and cleaned the AF mechanism located underneath the mirror, but that didn't seem to do the trick.

Last edited by LowVoltage; 08-30-2013 at 01:30 PM. Reason: spelling error
08-30-2013, 08:15 PM   #7
Veteran Member




Join Date: Jan 2007
Location: New Mexico
Photos: Albums
Posts: 1,125
Original Poster
QuoteOriginally posted by LowVoltage Quote
My K-5 auto focus was initially fine, as best as I can tell, but after having the camera for a few months it started behaving very strangely. CRIS spent more time with the camera than I did using it, but they never determined what the problem was. Eventually, Pentax replaced the body with a K-5 II, as the original was out of production by that time.

Even in good light (bright sun, contrasty scenes) the camera could not reliably judge distance of the same subject. I would auto-focus on a subject, say a tree or large street sign - usually at or near "infinity" distances, and each time the focus point according to the distance scale on the lens would be different. We're talking severe front and back focus issues of the same subject/scene over a dozen test shots. At first I was convinced my Tamron 17-50mm was the culprit, and that lens went to service several times, but Tamron insisted there was nothing wrong with the lens. They even calibrated the lens to the body, but that didn't seem to do it.

Then the body started doing the same weird focusing with both a Pentax DA L 55-300mm and my DA* 50-135mm. Both lenses had already been to CRIS to address focusing issues and they performed brilliantly when I first got the K-5. Then I tried an 18-55mm kit lens, a DA 35mm 2.4, and a Sigma macro - same focus problems. I became convinced the camera needed servicing. As I said, CRIS worked on the camera several times, but each time it came back it demonstrated the same problems. It's a long and sordid tale, but in the end the original K-5 went off to live at Pentax. While I doubt Pentax will perform an autopsy, I certainly hope they take some time to seriously consider the problem. I spent a fortune on shipping sending equipment all over the country!

Like I said, the K-5 was fine at first. Terrific, actually. It did everything much better than the K-7 that preceded it. When it started showing problems, CRIS even disassembled and cleaned the AF mechanism located underneath the mirror, but that didn't seem to do the trick.
It's an interesting saga, but you never told us how your K-5II performs. How would you rate the accuracy, consistency and speed of the autofocus?

Rob
08-31-2013, 03:28 PM   #8
Veteran Member




Join Date: May 2013
Posts: 304
Hi

I know K-5 II. AF is absolutely fine. If the scene has colors. I could never get to make it focus on white wall. Other than that it can lock focus in pitch darkness.

Cheers!

09-11-2013, 12:42 PM   #9
Senior Member




Join Date: Jan 2009
Location: Bar Harbor, Maine
Posts: 110
Hi Lowvoltage. Your story is very interesting to me as I have had a K5 for about 2 years and I believe in am experiencing the same issue with its auto focus perfomance. Lately I have started to shot portraits for seniors, and while I am able to get enough in focus keepers to pass on to the customers, I am getting a destressing number of shots in broad daylight, focus point right on the subjects well illuminated face where the camera does not achieve anything close to acceptable focus and then on the next frame it does!

I was thinking about sending the camera in to CRIS to be checked but I am disheartened that this didn't solve the issue for you. The altenatives are to get a K5 ii which is selling for a great price now and use my K5 as a dedicated M42 lens camera, or jump systems and go to Nikon, possibly a D600.

Initially I thought the issue must be user error (incompitence), but I am pretty sure my level of compitence/incompitence has remained stable!

Anyone with suggestions, I am all ears!
09-11-2013, 01:32 PM   #10
Veteran Member
cbope's Avatar

Join Date: Dec 2011
Location: Helsinki
Posts: 664
Those of you with focus accuracy problems, which focusing points are you using? It's well known that the outer focusing points are not very accurate and the center one is the most accurate of all. I use only the center focusing point on my K-5, with the focus-and-recompose method. My initial experience with the automatic focus point selection was not good and I almost immediately switched it to center only.
09-11-2013, 01:37 PM   #11
Senior Member




Join Date: Jan 2009
Location: Bar Harbor, Maine
Posts: 110
Interesting, I had not heard that. I'll do some work with center point and recompose and see if that helps. Still, pretty disapointing if I have to stick to center point and recompose. Thanks for you input!
09-11-2013, 01:41 PM   #12
Veteran Member
cbope's Avatar

Join Date: Dec 2011
Location: Helsinki
Posts: 664
QuoteOriginally posted by DougLee Quote
Interesting, I had not heard that. I'll do some work with center point and recompose and see if that helps. Still, pretty disapointing if I have to stick to center point and recompose. Thanks for you input!
I've been doing focus and recompose since the very first autofocus SLR which only had center point focus, so it's kind of ingrained. For those interested, that was the good old Minolta Maxxum 7000.
09-11-2013, 01:56 PM   #13
Forum Member




Join Date: Jul 2013
Posts: 69
Using center AF point only and recomposing has always been the way I was using AF . And I never had a problem with "erratic AF" "low AF accuracy" on K-5.
The other part of the story is that 90% of my glass is manual only.
09-11-2013, 02:13 PM   #14
Veteran Member
cbope's Avatar

Join Date: Dec 2011
Location: Helsinki
Posts: 664
QuoteOriginally posted by atarget Quote
Using center AF point only and recomposing has always been the way I was using AF . And I never had a problem with "erratic AF" "low AF accuracy" on K-5.
The other part of the story is that 90% of my glass is manual only.
Amazing! I also don't have any AF problems with my manual glass!
09-11-2013, 07:55 PM   #15
Forum Member




Join Date: Jul 2013
Posts: 69
QuoteOriginally posted by cbope Quote
Amazing! I also don't have any AF problems with my manual glass!
Cbope, I hope you realize that as a matter of fact AF is for idiots only ?
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dslr, k-5, k-5 ii, k-5 iis, k-5ii, k5, pentax k-5
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K5 poor focusing accuracy in anything other than bright sunlight? K5II any better? frstep Pentax K-5 18 03-19-2013 08:11 AM
Pentax K-5, K-5II and K-5IIs rear sync broken with manual lenses Nass Pentax K-5 17 02-25-2013 05:24 AM
K-5II focusing screen or sensor issue toukan Troubleshooting and Beginner Help 7 12-09-2012 12:14 AM
Fujifilm X-E1 or Pentax K-5/K-5II Snajder Non-Pentax Cameras: Canon, Nikon, etc. 39 12-06-2012 05:01 PM
From a K-7...K-30 or K-5II? Daemos Pentax DSLR Discussion 14 11-09-2012 07:04 PM



All times are GMT -7. The time now is 08:42 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top