Forgot Password
Pentax Camera Forums Home

Closed Thread
Show Printable Version Search this Thread
12-20-2010, 02:23 PM   #91
Senior Member

Join Date: Aug 2008
Location: Michigan
Posts: 176
I love my Pentax gear, not sure if I'd call myself a fanboy.

I've noticed this when I've shot in very dark or difficult lighting.

I shot a high school winter concert for a family friend, and had to dial in my DA 50-135 to -6 to get things close to right. I was using a monopod, and had adequate shutter speeds also. Because of this I did miss some shots, because her performance was near the beginning and I hadn't made any adjustments yet.

So... I thought, well I hadn't checked the focus adjustment on that lens since getting my new K5. I rechecked all of my lenses today. Zero adjustment needed for all.

I do use my 31mm a lot when out with friends at a bar or restaurant, and I get front focus in those situations also. But this is in very difficult lighting, so I try not to have unreal expectations. The thing is though, that the focus locks and is not hunting.

A firmware fix would be great, I'm still very happy with the camera, and am amazed by the improved AF and high ISO.


12-20-2010, 02:34 PM   #92
Veteran Member
Todd Adamson's Avatar

Join Date: Oct 2010
Location: Iowa
Posts: 722
QuoteOriginally posted by jsherman999 Quote
Todd, this image wouldn't strictly count as 'tungsten', would it? Looks like a lot of disparate light sources there. If the color-tied sensor is the problem, it might have been mitigated in those tests.

(plus, make sure that cat isn't peeing under your tree. He looks guilty.)


I suppose it could be counted as mixed light, but the tree lights were a very small contribution compared to the tungsten, I can assure you.

I do need to retest, though, because reading this thread it seems like the issue is inherent to the firmware? In which case, there should not be variability, am I right? I definitely had dead-on focus that evening, for most of my shots, and the ones that were off a bit were BACK-focused. So, either I am wrong in calling it tungsten source, or perhaps the condition only manifests in lower levels of light than I was using. I will say that my DA15 was not able to grab focus at all under the conditions, so I am calling it fairly low light.

At any rate, I was having success under conditions in which I would not even bother trying to get keepers with a K-7, so this reinforces Falk's point that you can still get lots out of this camera while waiting for the "fix," if indeed it's coming.
12-20-2010, 02:50 PM   #93
Senior Member
xGene's Avatar

Join Date: Apr 2008
Location: Toronto, Ontario
Posts: 151
Remember the old days?

Just a thought...: Does anyone remember the old film era? Does anyone remember using infra-red film either for professional reasons on just because it looked cool? (I know, I'm an old fart!...)
Does anyone remember that when you used IR film, you had to manually adjust the focus several feet from the focus point in your viewfinder to have a focused image on the film? I'm just saying, there seems to be some similarities here:

Infra-red => long wavelength, low temperature
Incandescent light => shorter wavelength (still long however) and a bit higher temperature, and lots of infra-reds are also produced...

My point is that it's in the same wavelength range and because this wavelength and color temperature can vary quite a bit with tungsten lighting (because of different filaments, overvoltages, undervoltage and by design as well), perhaps it is very difficult to "dial-in" a "universal" compensation algorithm... But again, I may be completely off the track...

BTW, I do use my primes mostly, in low/incandescent lighting. The only one that really gives me trouble is the FA*85/1.4. There is no amount of correction I can dial-in, it will always front-focus. The other ones, including the FA50/1.4 are spot-on 80% of the time with the K-5, which I consider quite acceptable, personally. The K-5 improved things a little however, which to me is an indication the SAFOX(+) works somehow, but perhaps not optimally yet.


PS: I'm one of the lucky guys who did not get a "stained" sensor either... My serial number starts with 3858, one of the latest batches.


Last edited by xGene; 12-20-2010 at 03:00 PM. Reason: Added PS
12-21-2010, 11:38 AM   #94
New Member

Join Date: Nov 2010
Location: Kolbotn
Posts: 4
Sorry to say, but this thread actually made my day. I've been trying to figure out quite some time why my K-5 won't focus where both my K20 and my daughters K200 will. And the frustrating part have been that next day everything seems fine. Now I can argue withe the dealer.

Last edited by Goethe; 12-21-2010 at 11:40 AM. Reason: misse the last sentence
12-21-2010, 12:10 PM   #95
Senior Member

Join Date: Feb 2010
Posts: 116
Original Poster
The thing is GOETHE that the K5 does focus very fast under nearly all circumstances but.....
not correct. Nearly no hunting but fast and decisive focus would let you believe everything is o.k. under tungsten light. But the result is not so well as it initially makes you believe. Pray for a good fix with all us PENTAXIANS that seem (too ?) loyal.
12-21-2010, 12:26 PM   #96
Veteran Member

Join Date: Mar 2007
Location: Boston, PRofMA
Photos: Albums
Posts: 3,053
I just realized this might explain why I got OOF shots w/ the da35 at a photo show w/ the K5. I had assumed it was because I fat fingered the AF/MF switch, but it kept lighting up the focused indicators. I'll have to see if I can undelete a few of them off that flash card...
12-21-2010, 04:18 PM   #97
New Member

Join Date: Oct 2009
Posts: 11
QuoteOriginally posted by jsherman999 Quote

Todd, this image wouldn't strictly count as 'tungsten', would it? Looks like a lot of disparate light sources there. If the color-tied sensor is the problem, it might have been mitigated in those tests.

(plus, make sure that cat isn't peeing under your tree. He looks guilty.)

I've sent my girlfriend jsherman999's reply to T. Adamson. Anybody knows she's refering about?:

'The cat looks like saying: oh my god, what the hell is this f... guy doing
with his f... camera, I'm really worried about his mental sanity..., could
someone go and get a doctor?'


Last edited by juekapasta; 12-21-2010 at 04:54 PM.
12-21-2010, 06:46 PM   #98
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863
From a German dealer in his forum:
Die Pentax-Ingenieure in Japan arbeiten mit Hochdruck an der Sache und bitten um etwas Geduld.
engl.: Pentax engineers in Japan are working flat out on the matter and ask for a bit of patience.

Original source:

Last edited by falconeye; 12-21-2010 at 06:54 PM.
12-21-2010, 07:08 PM   #99
Veteran Member
krebsy75's Avatar

Join Date: Jun 2010
Location: Chester County, Pa.
Posts: 804
My wife's K-r has this issue as well. Why do I feel like a beta tester for Pentax?
12-21-2010, 07:45 PM   #100
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 10,157
QuoteOriginally posted by krebsy97 Quote
My wife's K-r has this issue as well. Why do I feel like a beta tester for Pentax?
Doesn't matter what you buy, you are probably a Beta tester. I don't know if Pentax is significantly better or worse than the competition.
12-21-2010, 10:05 PM   #101
Inactive Account

Join Date: Sep 2008
Location: Cleveland
Posts: 132
My replacement came yesterday and I was able to spend a few minutes with it tonight. The sensor is stain free, so I'll move on tomorrow to repeating the AF tests. From some informal shots in low light, I did seem to have a FF issue that was best corrected at -6. However, I wasn't able to shoot in daylight to compare the results so I can't say for sure that that a different adjustment would be needed in different light conditions. I'll provide an update tomorrow.
12-21-2010, 11:39 PM   #102
Forum Member

Join Date: Jul 2010
Location: Madrid
Posts: 66
OK, since I did not get much of an answer from the Pentax distributor in Spain, I emailed Pentax Europe, and yesterday I got what I believe is the first official confirmation from Pentax that they are indeed working on the issue.

Here's the text:
Dear Sir,

Thank you for your enquiry.

Pentax is allready aware of this issue.
This issue has already been reported to our factory, and our engineers are investigating the case, in order to quickly fix it.

As soon as there is a new firmware-version that solves the issue, it will be published on our international website first:

Software Downloads : Support & Service : PENTAX

I hope that your question has been answered to your satisfaction.

Should you have further questions regarding this matter, please do not hesitate to contact us again. When replying, please make sure this email is included.

With kind regards,
Pentax Digital Camera Support Team
So now we know.
What I still don't get is why so many people seem to be unaware that their K5 has this problem...
12-22-2010, 12:27 AM   #103

Join Date: Apr 2007
Location: Sweden
Posts: 1,940
QuoteOriginally posted by Fer Quote
So now we know.
What I still don't get is why so many people seem to be unaware that their K5 has this problem...

The most logical answer is that not all cameras have the problem, I don't know if that is the case but I would think so.

Perhaps some part (light temperature sensor?) doesn't answer in time or initialize correctly on some cameras due to timing problems in firmware. So for the AF in some cameras it is always sunny. Or something, I'm just speculating and hoping for something like this which can be fixed in firmware.
12-22-2010, 01:39 AM - 4 Likes   #104
New Member

Join Date: Sep 2010
Posts: 20
Hola, como he dicho anteriormente, a TODAS las cámaras les ocurre.

Yo administro en España una tienda especializada solo en Pentax (La Tienda, y todas las cámaras que entran y vendo, son probadas por mi una a una y actualizadas el firmware, etc.

Y todas las unidades probadas, incluso de las ultimas con numero de serie: 39XXXX, todas, bajo las misma situación lumínica controlada que tengo, y que se reproducir, actúan igual todas las K-5.

El porque muchos no lo detectan, es debido a varios puntos:
- Solo es con objetivos luminosos, con enfoque de tornillo. (No todo el mundo tiene limited, o lentes luminosas)
- Solo es con ciertas tonalidades de tungsteno.
- Solo ocurre en situaciones con muy baja luminosidad, y en el umbral en el que no se activa la luz de ayuda. Si se activa la luz de ayuda al enfoque, el enfoque es preciso.
- Además en cuanto el diafragma se cierra desde f/5.6, la profundidad de campo absorbe el front focus, siendo inapreciable.

Las situaciones en las que se da es muy bajas.

Como dije, realice un estudio que reporte a Pentax, con toda la información, y se de mano directa de Pentax España y Europa, que están trabajando en ello, y que la solución vendrá por una actualización de firmware.

Saludos cordiales...
12-22-2010, 02:52 AM   #105
Veteran Member
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,863
QuoteOriginally posted by Pentaxeros Quote
Saludos cordiales...
Thanks again.
You're making the most useful contribution here.

And it is the first time where I see the forum's translate feature to actually be an added value: not only can I understand what you say. But additionally you are posting here at all which is a great bonus.

Kind regards,
Closed Thread

  • 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, conditions, dslr, focus, k-5, k-5 ii, k-5 iis, k5, lens, light, pentax k-5, tungsten
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
Front Focus and tungsten light question Big G Pentax DSLR Discussion 8 01-18-2010 12:25 PM
released Kx firmware 1.01 anyone cares? Mystic Pentax News and Rumors 4 12-05-2009 09:19 PM
Can K20 be adjusted for indoor Tungsten light? philbaum Pentax DSLR Discussion 12 07-22-2009 05:40 AM
A ship in bad light mingdie Post Your Photos! 11 08-07-2008 03:52 AM
Tungsten light option k100d super problem? demoleman Pentax DSLR Discussion 17 02-18-2008 04:58 PM

All times are GMT -7. The time now is 06:10 AM. | See also:, 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?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]