K5 and low light auto focus errors?

[lummi_pannasso1]

<p>Anyone else seeing auto focus errors with there K5 in low light conditions? I was shooting at a christmas function and the K5's auto focus was completly useless. I had to switch to manual focus to get a decent shot.</p>

 

[andy_coach]

<p>Mine seems to work OK in low light, w/out the AF assist beam. Mostly with 50/1.4 and 18-50/2.8.</p>

[shots worth sharing]

<p>Mixed results here but I tend to suspect operator error before equipment inadequacy.</p>

[lummi_pannasso1]

Defiantly equipment inadequacy. Consistently front focuses about a half meter. Auto focus adjust does not seem to help.

I have compared results with the k7 and the k7 does much better in low light. It did front focus a bit but was corrected

with a -5 focus correction. This was with a da 40mm at f2.8.

[snik75]

<p>If it does it with all lenses, it could be a problem for repair or replacement. If only one lens, perhaps adjusting the AF would do the trick? I have "rescued" a few lenses that way.</p>

[k_kakkinen]

<p>Lummi...<br>

I agree with you....took pictures with my new replacement K-5 during Christmas Day gathering in low light conditions and would very much agree with you when you say that the camera front focuses about a half meter.... In my case I took three pictures of my niece and her boyfriend and everytime I focused on her face and non of them were sharp in the face area...instead, when I was reviewing those three pictures for harpness...the "sharp point" was about a half meter in front of the objects....In the end, I focused manually since I saw that the meter indicator on the lens was "way out" of distance sometimes.... At DPReview a person by the name of "hexar" have written about his focus problems too....</p>

[lummi_pannasso1]

<p>Thanks Kari, interesting read.<br>

I emailed Pentax a couple of days ago about my problem and have not recieved a response as of yet. It seems to me that this might be fixable through firmware as my K7 does not seem to front focus as bad.<br>

Are you returning your K5 or keeping it? As I still have my K7, I think I'll return mine and wait to see what they do to fix it. Too bad as the K5 is a vast improvement over the K7 in every other way.</p>

[scott_fraser4]

<p>I'm on my second K-5 after I returned the first one due to the stains on the sensor. The first one I spent an age calibrating all my lenses - under dim tungsten light. 15mm got a +3, 21mm got -5, 70mm +6 and the 100mm macro was bang on. The 40mm front focuses so severely that it was still out of focus with -10.</p>

<p>Btw, I haven't ever seen this reported, but as far as I can see the "Apply all" is like a camera setting and the "Apply one" a per lens setting that can both be used at the same time and so you can set the camera to -10 and the lens to -10 to get more adjustment. My old body seemed ok with the 40mm with "Apply all" set to -10 and "Apply one" set to -5, the new body is still a few millimetres front focused with both set to -10.</p>

<p>I just did a quick recheck, my 15mm, 21mm, 70mm and 100mm focus ok with minor tweaks on the new body.</p>

<p>From reading the forums, many people don't have this problem at all and some do which would suggest that only particular combinations of light + target + body + lens. I've seen at least some people claiming SDM lenses are not affected.</p>

<p>Rumour is that Pentax are working on on a firmware fix which fix up the affected k-5 + lens combination.</p>

<p>I did wonder if the short focus throw of the 40mm is the problem. But for now I'll use f4 and -10 adjustment to both sections if I really need it under tungsten. My other lenses are fine, so there is nothing fundamentally wrong with the body.</p>

[lummi_pannasso1]

<p><em>Btw, I haven't ever seen this reported, but as far as I can see the "Apply all" is like a camera setting and the "Apply one" a per lens setting that can both be used at the same time and so you can set the camera to -10 and the lens to -10 to get more adjustment.</em><br>

Interesting, thats something I didn't know or try. I tried "Apply one" to the da 40mm and like you, couldn't even get close to proper focus<em>. </em>As this is currenttly my farorite lens I didn't bother with my 21mm or 35mm. My 16-50mm da* was also severly out of focus so I'm not convinced that SDM lenses are immune.</p>

[ukhov]

<p>A few cood man and zoom lens go wrong, not talk to be a "star" !?</p>

[audun_sjoeseth1]

<p>My K-7 needed -9 to focus correct with my AF-lenses. I sent it in, and the Pentax service (here in Norway) adjusted the AF-sensor to the correct position. I didn´t have to pay anything for the fix.Now the camera fokus perfect.<br>

If I have any problem like that when I get the K-5, I´ll sent it back too.</p>

[k_kakkinen]

<p>Lummi...<br>

At the moment I'm not going to sent it for service....yesterday I calibrated my 16-45 lens and I had to adjust it to -10 before I "saw something" closer to "the truth"...so during the New Year weekend I'm going test this calibration and if it's not to my liking I'm going to contact Pentax Service here in Sweden for advice....</p>

<p>Scott...<br>

Hope the rumour you mention really is going to happend</p>

<p>A reflection to all this... I know that the sensor plate is a "moving" device...BUT, is it supposed to "move" when one press the shutter button while moving the camera from side to side in a little "harder way" ??? Well, I tested this with my camera and it sounded like the sensor plate was "moving" from side to side in the camera.... thought that when one press the shutter button the sensor plate is locked "in the middle" and from there it moves against any camera shake....</p>

<p>Hope not this has anything to do with "bad" AF....that it's only in my head...</p>

 

[mountainvisions]

<p>Actually, I do not think the Apply one and apply all are cummulative.</p>

<p>I think you can apply all and then apply one for single lenses. So if the camera has a focus issue with all but one lens, you can hit apply all, and then apply one for the lens that doesn't have the issue. Generally speaking on my K20D and K-7 I never found it to be as simple as one setting for all lenses. And I was ok with that because I wanted perfect focus from each lens so spending 5 minutes on each individual lens was OK with me!</p>

<p>This has been covered for the K20D on various forums, and it wasn't cummulative. If the K-5 is different I appologize!</p>

<p>As a note, my test K-7 didn't focus correctly with ANY lens I mounted to it. But all were within the tolerances of the adjustment system. With my personal K-7, before I sent it for shutter replacement it worked the same, all lenses needed minor adjustments (less than +-7) but when it came back from repair for the shutter the AF system was messed up. So much so that with my DA 21mm it would focus in two different spots depending on infinity or near focus start points.</p>

<p>Don't be affraid to adjust your lenses using the custom menu, actually, even if your camera seems perfect, there is no harm in calibrating them. Even if they are only -+1 off it will make for much sharper images. If they are a half foot off, than I would definitely calibrate. However, if your MODERN DA/FA glass isn't calibrating within the adjustment range of 10, you need to send the camera back. With my shutter repaired K-7 my 50-135mm was not within calibration at -10!!! I believe it needed like -12 or -13. This was clearly an issue with the focus system as the DA 50-135mm is a currently manufactured lens. That and the DA 21mm issue were proof enough I had a problem that needed repair.</p>