[znieh]

1) It's interesting that still some confirm a serious issue and some do not. The one's who do complain say it's so obvious even an i*iot would see it. Others start doing semi-scientific tests under special, more or less controlled conditions and sometimes see something, sometimes do not.
After having possessed three K5 (and one D7000 in between) within the last two months (and detected additional four K5 with the same issue in the store), with around 6000 pictures shot, and belonging to the group of i*iots that do see the issue on all these eight K5, I believe that it is exactly as we can see in this post: Some have the issue and some do not. (Among them in this thread who are not sure: with some testing you always can prove something is not as you expect it to be, just test hard enough! But this is NOT what bjan had in mind when he started this thread about a severe FF issue).

2) The new FM 1.02 does not fix the issue. I don't know how YOU see it, but I believe Pentax tried to do something about the FF. My K5 used to perform ONE focus operation, in rare cases maybe two. Now it does the first focus step as before, and then very often a second, even third smaller one until it finally locks. This is different than before. But: It did not solve the issue.

3) From these two statements I conclude that we have a hardware issue: Not everybody has it, and a firmware update does not fix it properly. From my job in electronics I can tell you that in 2010 we (global markets) have had massive quality problems with fake electronic components (all global players have global sources that went short with deliveries in the ramp-up situation after the crisis - so they got parts from other, presumably safe sources). Never this fake issue had such a dimension compared to this last year. Why Pentax should not be affected? This is my personal explanation.

4) I for my part today returned my 3rd (or 4th?) K5 after having tried out 1.02. I was as loyal as one could be. And if Pentax some day delivers a good batch to my store, I will get me a new one. I do not blame Pentax if there is a fake issue, as this is a problem that affects all manufacturers. And in practice, it was possible to use the preview CAF to get the right picture, but after thousands of shots my experience is that I just do not want any more to be trapped with a 1500 $ camera in that situation where I hate it to be too late with the contrast AF of preview. Too many shots that I missed due to being too slow after repeating the pic because of FF with the viewfinder. (And again: FF in this thread is meant to be really bad FF, not FF that can be adjusted)

[soaks]

Installed firmware 1.02 I was hoping for some improvement in the focus under low tungsten light. I think it actually made mine worse. I had some front focus previously but it seems to be more pronounced than before. Seems to have also affected the WB for photos in daylight. Anxious to see what others are experiencing.

[Tommot1965]

Hi all, after a bit of a 'fractiousness' on Flickr with Rupert, about a tongue-in-cheek comment I made about how, against the odds, I've got a camera (K-5) and lens combination (Tammy 70-200 f/2.8) that could actually focus, he asked me to post here with results from a low light tugsten focus test. The reason I'm doing this is not to start more disagreement, but merely to show that it is possible to get a K-5 that works (it's not all doom and gloom)
So a quick intro to me, I've got 25 years of engineering experience and have worked in the movie industry for a while (as well as military and high end telecomms), so I have a fairly methodical approach to look for and solve problems. As I think this is probably my first post I thought I'd better give you a little heads .... I realise this doesn't mean I DO know what I'm talking about, but I've got a fair idea.
So first, a shot that was taken with the 70-200, and a 100%ish crop. I took two lenses, this and the 28-75 f/2.8, before I went I checked for ff/bf, in daylight, and adjusted both lenses slightly (as I had to do for the K-7 beforehand). I should report that the adjustment was pretty much the same for both cameras, but the 28-75 was pretty much spot on anyway.
The good stuff
200mm f/4, ISO 400. 1/500th sec


and the crop


So anyway, enough of the that stuff.

This I posted in response to a question from Rupert
ISO160, 1.0s, tungsten lit with tungsten WB (and a bit from the tv)
Tamron 28-75mm f/2.8 at 75mm and 2.8, about 3m away.



The focal point is at the top of the radiator
and a crop


I should also say, the focussing assist light did come on when taking this shot. Focus was hit first time and quickly.

Please feel free to fire any questions or comments, but I'm off to bed now (in the uk) so it might be a while before I respond.

your not gonna see the issue at that distance { 3 metres} while at F2.8..as the DOF is too great, at 180mm

try it at 1.5 metres from the subject {75mm F2.8 } ..the DOF is only 40mm . see it is focuses correctly still.

[pcarfan]

Just as an FYI, as I had contributed to this thread in the beginning. I just packed back my K-5 and I will return it over the wknd.

The K-5 is indeed an incredible camera for high iso and eventhough I haven't tested it well, will have great DR, but the inability to focus well under low tungsten light and the inconsistant flash exposure has frustrated me too much when I used it for the NewYears party.

I have tyhe K-7, yes it gets a bad rap for the sensor, but it is a true joy to use that camera. perfect P-TTL and perfect focus under low light. Yes! it sucks at high iso but I will live with that.

But, the K-5 when it works in low light is nothing sort of a miraculous camera...I will wait for Pentax to either announce a fix or release a firmware than me taking the risk of holding onto this camera after the return period is over, as I already have the K-7. I can't wait for pentax to do so, as i will order it the very next day.

I don't want any arguments over this...I agree with those who disagree with me and I agree with thos who agree with me as well...it's just an FYI.

[Zugzwang]

Well, Pentax finally emailed a response regarding my poor AF, took them over a week.
Not what I was hoping for but at least it's a response. Here is what he wrote.

Dear Customer,

Thank you for contacting Pentax regarding your K-5.

Autofocusing in low light is often a test for any camera. Using a fast shutter speed to freeze the subject means that the camera either must use a larger lens aperture and/or raise the sensitivity to counterbalance the reduced amount of light striking the image sensor. Also, the lower the light, the harder it is for the camera to confirm focus. On the other hand, using a slower shutter speed to compensate for low-light levels often means a moving subject will be blurred, so while the camera may confirm focus correctly, it's entirely possible that camera shake or a low shutter speed is causing the poor performance.

Another factor which adds to the difficulty of shooting in low-light is the fact that as the lens is zoomed out (to bring the subject closer) the maximum (widest) available lens aperture becomes smaller, thus further reducing the light needed to record a good image. If flash cannot be used, the best advice is to raise the ISO as needed and if a DSLR is being used, to consider using a lens with a larger maximum aperture (i.e. our DA* 50-135mm f2.8) and using the lens at less than maximum zoom extension. The wider the angle, the easier it is to stabilize the lens and due to increased amount of light.

It is also important to ensure that you are using the AF assist light in low light scenarios. On a further note, if the light is too low it may be necessary to use a tripod. If you have followed all of the precautions above and are still concerned that the camera is not performing as it should, I recommend that you send us test photos for review. Please send original jpeg or raw files to info@pentax.com that exhibit the problem.

The latest firmware version for the K-5 is v1.01.

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

[PhilippeG]

@Zugzwang: so they advise you to go learn proper photography or buy a better lens, and don't admit there may be a real issue. Wow, hard to believe!

And what about using the focus assist light at concerts or in a church?

[WerTicus]

Apparently the new firmware reduces the threshold where the AF lamp comes on... this might help...

As i had perfect focus with AF lamp on 1.01 but if it was just light enough that the lamp did not come on then i would get front focus.

I have not yet calibrated any lenses yet though. So its a bit hard to expect them to focus correctly till i do this.

---

Last edited by WerTicus; 01-06-2011 at 08:30 PM.

[fccwpe]

As i had perfect focus with AF lamp on 1.01 but if it was just light enough that the lamp did not come on then i would get front focus.

Exactly. without the assist I have this issue as well. Taking a picture of a white or light colored object in low light the K-5 will not focus right.Under the same light with a dark colored object the assist comes on and the focus is perfect.

Don't really know what to make of it....

[WerTicus]

we need to be able to program the raw fx button to be a manual af lamp button!

[Wheatfield]

Exactly. without the assist I have this issue as well. Taking a picture of a white or light colored object in low light the K-5 will not focus right.Under the same light with a dark colored object the assist comes on and the focus is perfect.

Don't really know what to make of it....

Light coloured things are light because they reflect more light. Dark coloured things reflect less light. Hence something dark in front of the camera will cause the AF light to activate sooner than a light coloured object.

This also is why we see noise in shadows but not bright areas.

[Fer]

Well, I tried v1.02 and no improvement whatsoever. I still can't believe that Pentax has released a new firmware version that doesn't fix this huge issue they've known about for at least two months. To me, this suggests that it cannot be fixed or that it's so hard to fix that only a partial solution will be achieved.

At this point, I really have a good mind to return my camera and forget all about it.

[raist3d]

Since 1974 I've rarely had a "perfect" camera. My Oly OM-1 (bought new when c
...

So no, I don't see this as that big a deal. In the grand scheme of things, I see this as same old, same old. I've dealt with it with every camera maker I've bought from.
What professionals do is figure out how to get the pictures they need to get with the equipment they have.

Besides, it's so much fun to tweak you peoples' noses until you are frothing at the mouth and then watch the resulting apoplectic histrionics that I just can't help doing it.

Enjoy photographing your focus charts, I believe I have a glamor shoot for a Valentines Day gift today.
I love my job.

The problem here is that this is not a problem *for you* Have I read that "Pentax autofocusing is so bad it's not recommended for professional use" and believed that, yes, I wouldn't have bought one. Why else go for one coming from another system that had AF frustrations whose new camera uses an outdated sensor but probably can focus better?

But of course you espouse the "professional" mantle here like the battle tested veteran who just happens to know how things are done and knows how to do it, from what ends up being your limited perspective of standards you are willing to put up with combined with your needs and preferences. Hell, I am happy you don't have an issue with this. But there's no need to then dismiss those who do as people who don't have legitimate concerns or needs, and that's still understanding and even agreeing with you there will be a set of people on the net that will definitively blow things out of proportion.

For your information, since you seem to enjoy doing little man attacks, I haven't photographed a single focus test chart. There's no need to, it's that obvious. Of course, looking at the history of some of your posts, you have also complained about things of the cameras of this brand, so it looks like when other people say something they are whining, but when you do it, apparently it must be the voice of experience or something.

For someone who seems to enjoy their job and is so professional I notice a distinctive lack of photographs, but maybe you have an awesome portfolio somewhere. Who knows right? After all I don't know you and you don't know me. Maybe we both vastly underestimate each other.

- Raist

PS: Glad to hear you really enjoy your job. Most people that love twisting other people's noses "for fun" are very insecure.

[raist3d]

Well, I tried v1.02 and no improvement whatsoever. I still can't believe that Pentax has released a new firmware version that doesn't fix this huge issue they've known about for at least two months. To me, this suggests that it cannot be fixed or that it's so hard to fix that only a partial solution will be achieved.

At this point, I really have a good mind to return my camera and forget all about it.

Got a good word from some other forum with some contacts with Pentax that Pentax Japan is aware of the problem and they are working on it. Hopefully a firmware upgrade is all that is needed.

It's quite possible (for those who see no problems with their cameras) that this varies per lens. Or of course, that there are different batches of cameras with/without the issue.

- Raist

[StigVidar]

Got a good word from some other forum with some contacts with Pentax that Pentax Japan is aware of the problem and they are working on it. Hopefully a firmware upgrade is all that is needed.

It's quite possible (for those who see no problems with their cameras) that this varies per lens. Or of course, that there are different batches of cameras with/without the issue.

- Raist

Do you have a link to this "other forum"?


It is lens dependant and in fact focal length dependant with the same zoom lens. So different views on this problem is quite obvious.

[Bredoteau]

My friend's Nikon D90 AF assist lamp is almost always turns on in low light, even when far from the Pentax does not work. I think this may be one of solution ...