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04-12-2011, 11:27 AM   #16
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QuoteOriginally posted by ramones1985 Quote
This is NOT THE SOLUTION.

I have a KR, not a K5!!

And i don't want buy a K5!
I wasn't talking to you!

04-13-2011, 07:15 AM   #17
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I disagree. With a custom white balance the camera determines the color temperature of the incident light. Once the camera knows the color temperature it should be able to compensate accordingly to ensure accurate focus.

QuoteOriginally posted by doozer Quote
@krebsy97: obviously, it is not the white balance itself that makes the difference here (as this is a post-processing step anyway). The hypothesis is that the K-R uses the whitebalance setting information to adjust focus. It could very well be that using a custom white balance setting does not lead to this focus shift.

And since I can get better results by applying tungsten white balance, this is definitly not total nonsense - we might just not completely understand how it works and what the camera makes out of the WB setting.
04-13-2011, 08:24 AM   #18
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sure it does determin the color temperature with a custom WB, the question is, whether it then uses the information to adjust the focus mechanism... The AWB also tries to find out, what the color temperature is (although it is not as exact as the custom WB) and still the problem appears...

you could just try it out for yourself with the tungsten setting. I know that it does improve things in my case.

Or just believe what you want to believe.
04-13-2011, 09:04 AM   #19
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I don't have the camera any longer. A focus test comparing custom white balance and tungsten lighting is in order.

QuoteOriginally posted by doozer Quote
sure it does determin the color temperature with a custom WB, the question is, whether it then uses the information to adjust the focus mechanism... The AWB also tries to find out, what the color temperature is (although it is not as exact as the custom WB) and still the problem appears...

you could just try it out for yourself with the tungsten setting. I know that it does improve things in my case.

Or just believe what you want to believe.


04-13-2011, 01:35 PM   #20
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I did this test last night and will post the results tonight. The AWB shots showed quite bad FF, the Tungsten shots showed milder FF.

Manual worked beautifully, although the test target was hard to see clearly in dim tungsten light. I noticed that the focus confirm came on when the target was not in focus, then came on a second time when I twisted the focus ring back to correct by concentrating on the image alone.

Another thing that worked was to select another focus point positioned over something a little behind the target... A sort of guesstimated, on-the-fly compensation for the FF.

Working with the test target clearly showed the FF problem. It isn't an issue for my street shots or nature shots, and hasn't been much of an issue for my dim, interior domestic shots.

I look forward to the firmware update, but I am enjoying this camera immensely.

The bigger worry is LBA.

Last edited by Taobat; 04-13-2011 at 01:38 PM. Reason: Fixed a garbled sentence
04-13-2011, 04:22 PM   #21
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I also got this advice and have compared the AWB and tungsten WB under my CFL lighting. As far as I can tell the WB change does not make any difference (or a very marginal difference) for me. FF is still there.
04-14-2011, 12:21 AM   #22
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@doozer: because the manual lens I've got is more for secondary use, and not indoors where there's artificial light.

I don't really expect to be giving up my K-r, so I am on the fence about getting the focus screen... However, if the front focus isn't fixed, I might re-evaluate keeping the camera - not that I know what I'd replace it with.

Picked up a K-5 on behalf of my brother this past weekend. Wow. *Very* nice camera. Don't think I can justify the expense for a hobby at this point. :-/
04-14-2011, 12:29 AM   #23
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Ok. Based on abcdave's report on KatzEye, I probably will order a screen once I get my income tax refund, regardless of the firmware situation.

04-23-2011, 08:53 AM   #24
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I tried this work around and I have to say it helps. It isn't perfect by any means, but it does help "reduce the occurrence" to a relieving degree. I figured I'd post up the evidence here.

First picture is with Auto White Balance. Next picture is with the Tungsten White Balance. Be advised my lights are not actually tungsten, they are the common found-in-walmart type of energy saving CFL that has the same yellow tint as tungsten.

These photos are 100% crops taken at 1/60th handheld ISO 640 at 1.4 using a Sigma 30mm 1.4 (wide open).
Focus AF point is center.
The cap is tilted at a good angle to show the FF effect. There is still some front focus with Tungsten White Balance, but as you can see with the 100% crop, it is minimal.

Regardless, the necessity of a firmware fix is not negotiable if Pentax expects to save face. This is an awesome camera if it weren't for this.
Attached Images
   
05-06-2011, 07:59 AM   #25
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Totally agree Bob.

My observations support yours, though I find the tungsten WB fix less useful in the mixed/CFL lighting where I have seen the problem when the subjects are in the 1-5 meter range.

FF remains severe under those conditions even with WB manually set to Tungsten (or fluorescent--and I tried ALL the settings.)

I remain hopeful that Pentax will offer real solution, firmware or hardware. If they don't, it will mark them as an organization with no collective sense of honor and no sense of obligation to their customers--an organization that cannot be trusted.

Having invested close to a thousand dollars in this system, I would consider this a costly lesson. I would certainly not put more money into it, or buy anything from Pentax unless they rectified the problem and proved themselves worthy of trust.

I suspend judgment until September 9th. In the meantime I will not make additional lens purchases outside of the very cheap used category and keep my eye on developments from Canon and Nikon.
05-06-2011, 08:11 AM   #26
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That statement by Pentax to offer a work around instead of a fix is pretty disappointing. I have really jumped all in with Pentax, but I am starting to get a little ticked with them. Maybe there's a reason everyone on earth has a Canikon.
05-06-2011, 08:16 AM   #27
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if you have mixed lighting, the AF system can be absolutely useless. i had large windows letting in daylight and mixed cfl track lighting in this large room i was taking pictures of cars in. white balance hell aside, autofocus was next to impossible. i had to continuously stop after each photo, check preview to confirm focus, then switch between AWB and tungsten, retake the photo and sometimes neither would even work. i ran this by pentax a few days ago and was told to use manual focus.

QuoteQuote:
In the type of mixed light shooting conditions you described the only practical solution might be to use manual focus.

If you are in need of further assistance, please respond to this email or call our technical support center at 800-877-0155.

Sincerely,
Randall S.
Pentax Imaging Technical Support
05-06-2011, 02:20 PM   #28
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I must be in a crap mood today because I am going to inject my opinion into this thread. For a little perspective, the wavelength issue (tungsten vs. fluorescent vs. daylight vs. <put favorite light here>) is VERY old news as far as AF goes and is/has been an issue to some extent across brands. So to make it real easy, I will offer you $0.10 on the dollar (based on the current body-only price at B&H or Adorama, whichever is lower) for your defective K-r camera bodies to take the junk off your hands. After all, that is all they are worth if they don't AF properly and as we all know AF is the ONLY valid measure of the value of a camera.


Steve

(BTW...I am serious...first 10 cameras only...you pay shipping and insurance...be sure to include batteries...)

(...does primarily manual focus work and am REALLY looking forward to the great high ISO performance...)
05-06-2011, 03:20 PM - 1 Like   #29
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You are absolutely right, Steve--The high iso performance is really fantastic.

The AF is fast and usually accurate. You will be thrilled.

I love the ergonomics of this camera. It fits perfectly in my hand and I find all the controls are easy to operate with small motions. I rarely use my left hand for anything but adjusting the lens and supporting the camera/lens. changing mode, ISO, WB, drive mode, exposure compensation, aperture and speed can all be done without repositioning my right hand or taking my eye from the viewfinder.

I haven't had any problem with the e-dial and the whole camera feels very solid-Canons and Nikons in the same general price range feel very shoddy in comparison.

It's really a fantastic camera--as long as you don't need it to work in the conditions that make it fail. Unfortunately, these conditions are not that uncommon and it really does fail in them. It's something that should be fixed.
05-06-2011, 03:57 PM   #30
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IMOO I think the FF in tungsten lighting focus issue is a quality control issue. It seem like some people have gotten copies of the KR that work fantastic while other the focus is way off. My 6 year old DL was able to get sharper focus than my brand new KR in both MANUAL (not relying on focus confirm light) and auto focus.

The KR was sent to CRIS and is currently in shipping so I'm keeping my fingers crossed that they were able to adjust it.
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