[Philoslothical]

I currently have 4 lenses; the kit 18-55, the DA 40mm 2.8, an older 35-70, and a Sigma 70-300. Results are quite similar among them.

This doesn't sound like the typical tungsten issue, which usually shows up using faster apertures than most of these lenses are capable of. The 40mm wide open might reliably produce the issue. Usually it's only a problem when going faster than about f./2 though.

You said in your post that you're using both a tripod and the SR function of the camera. This isn't a good idea, as the SR mechanism can actually cause some softness if it has no shake to compensate for.

If I had to guess, I'd say it's likely that the two copies you've tried are miscalibrated. It's some really crappy luck, but it's not normal for the K-r. If you can afford the upgrade to the K-5, go for it, it side steps these problems and gets you a better camera as well.

@Steampunk - by all means get a split prism focusing screen for your K-r! There are good quality ones available from focusingscreen.com as well as Katzeye Optics and you can also pick up cheap Chinese ones on Ebay, if you can't handle the price of those. They won't be quite as good, but some people have reported they're still better than the stock screen.

[garyk]

Change brands. I was fed up with the focus issues. I hated to but when I changed it all went away. No more Af problems or any other problems. And I had the k-5. Do not think if you change to the k-5 it will magically go away. It won't.

[morpho]

I don't know if the OP is a newb, but i am, and therefore i am more likely to blame the guy behind the camera first, and the camera or lens later.

- Are you able to achieve a good focus manually or is it simply impossible to ever achieve critical focus?
- How is the Sigma AF @300mm?
- Have you tried turning off the big red distracting lump in your viewfinder? It's sometimes so big it's not easy to tell what you're really focusing on.
- I don't know if the focus points are selectable on the K-r, but if they are...which one are you, or rather, your camera, using?
- Are you absolutely sure you're doing everything right and not messing up in some fashion?

[DarrenCax]

Oh geeze...sorry my previous post was so jumbled. I guess it wanted HTML?

Anyway, I got the K-5 recently. First impressions were pretty poor, but once I upgraded from 1.01 to 1.13 the focus is spot on! I took the camera to work and used my 30-70 lens and had no issues. Focus was spot on, clearity and noise were about what I expected (decent lighting, ISO3200. freehanding) I really wasn't wanting to spend this kind of money on a camera, but honestly if I were to switch brands, I'd probably spend about the same after getting the camera and new lenses...

On to the other questions (and I'll confirm the spacing is better ^^; )

morpho - I'm not a supreme expert, but I have been into photography all my life and it is more than a hobby. Plus I didn't have the issues until I switched to the K-r... Focusing was always off, freehanding or using tripods. The Sigma lens is OK; a bit blurry at 300mm but I rarely ever use/need it. I've never gone without that focus indicator as I find it very useful, personally. I always set my cameras to point/spot focusing so I can pick exactly what it focuses on. And I'm certainly up for being proven wrong but I feel quite sure I'm using the camera correctly.

garyk - I may go back to Nikon if the K-5 gives me any issues, but I've been pleased with it today.

Philoslothical - I definitely see it more with the faster lens, but all the lenses seem to suffer to some extent. Even using the K-5, my 35-70 lens seems to focus much better. As for the tripod/SR pictures, I think you read it wrong or I typed it wrong. Yes, I have SR enabled normally, but when using the tripod I either use my remote or the self timer (as you know, disables SR). Now I very well could have had miscalbrated K-r's...

-- edit --

Just a little update. After this post I grabbed my pancake lens and started testing it. It does front focus ever so slightly. However, I tuned it to -2 and it seems to be spot on. My Weekend is on Tuesday and Wednesday so I suspect I'll do some "official" testing then.

---

Last edited by DarrenCax; 03-04-2012 at 08:38 AM.

[Verglace]

I had the same issues, I first got the K-r had af issues, returned it 4 months later and upgraded to a k-5. Was happy with the autofocus of that, especially with the firmware updates. I am very happy with the k-5 itself as a body, especially when Im only shooting static objects and available light photography. If you intend to use external flashes prepare to run into some issues

[geru2000]

Change brands. I was fed up with the focus issues. I hated to but when I changed it all went away. No more Af problems or any other problems. And I had the k-5. Do not think if you change to the k-5 it will magically go away. It won't.

....and neither will changing brands make it magically go away.

Need proof just go hang in the Nikon and Canon forums on the other site.

Fact is, it doesn't matter what brand you own it's possible to get a unit that suffers from a focus problem of some kind no matter how intricate the system or the brand.

[ablundon]

With my K-r I had to sent it in to get the focus calibrated. With the kit lens even a -10 on the focus adjustment was not enough. When I got it back from service, I was able to dial in the focus pretty accurately. At the time I thought it was tungsten related, but in hind sight...I think it was that the focus was out of calibration.

AB

[Mr Spocko]

....and neither will changing brands make it magically go away.

Need proof just go hang in the Nikon and Canon forums on the other site.

Fact is, it doesn't matter what brand you own it's possible to get a unit that suffers from a focus problem of some kind no matter how intricate the system or the brand.

I think Pentax have the prize for most AF problems v other makers. It's true that all makers have this to a point ie lemon bodies. But 3 K-r's later and I'd say it's a bit more than a bad copy.
The newer SAFOX is broken basically a flawed AF Module that will be retired with the next batch of cameras, of that you can be certain.

Pentax are never upfront about these things for fear of hurting sales. They add their "silent" updates in firmware to fix issues they don't even admit which is fine but fix this one they can't
I'd wager Canon and Nikon are likely to be quite a bit better for AF all round, but don't take my word for it play with a few and enjoy accurate AF "most" of the time

[Philoslothical]

It'd be really nice if someone would just ban this troll, since all he does is come by once in awhile to dredge up old topics with more inflammatory crap about Pentax.

[Mr Spocko]

It would be really nice if you accept that people have views and you can be adult enough to agree to disagree.

[foggyday]

Dear Spoko,
After sending my Kr back twice I thought that they had fixed it however shots in tungston lighting were still poor untill using it in Egypt.( different phase cycle to the UK)I had no problem with that at all but using the kit lense the camera has decided to just lock up and keep firing the shutter about 20 or 30 times (lense removed and contacts cleaned ) camera or lense not dropped or damaged so what next ?.The only answer is that the product is as bad as anything produced and anyone still defending it and then claiming all adverse comments require the Troll lable must start to see that three strikes is bad news. why are my other Pentax cameras still ok after 30 years plus and that was the reason I purchaced my Kr thinking the quality was to be the same. One of my cameras was used in Inner Mongolier 5c am 28c pm filming the last of the Qj steam locos for over two weeks without any problems in poor conditions so why doesnt this perform in good conditions. I do not wish to turn my back on the brand but I think the problems extend beyond camera shake or the jump from film to digital.

[foggyday]

Dear Spoko,
After sending my Kr back twice I thought that they had fixed it however shots in tungston lighting were still poor untill using it in Egypt.( different phase cycle to the UK)I had no problem with that at all but using the kit lense the camera has decided to just lock up and keep firing the shutter about 20 or 30 times (lense removed and contacts cleaned ) camera or lense not dropped or damaged so what next ?.The only answer is that the product is as bad as anything produced and anyone still defending it and then claiming all adverse comments require the Troll lable must start to see that three strikes is bad news. why are my other Pentax cameras still ok after 30 years plus and that was the reason I purchaced my Kr thinking the quality was to be the same. One of my cameras was used in Inner Mongolier 5c am 28c pm filming the last of the Qj steam locos for over two weeks without any problems in poor conditions so why doesnt this perform in good conditions. I do not wish to turn my back on the brand but I think the problems extend beyond camera shake or the jump from film to digital.

[Mr Spocko]

I have heard of some users with mirror issues (not just the K-r) but flapping mirror when the camera is inactive or should be.
The temp of the light seems critical to the AF accuracy so it's possible to be in higher kelvin light and not have the problem, but all my bodies showed problems in halogen/tunsten/energy saver bulbs ie 2700k around there up to say 3200k I am just making a guess on that. I am not aware if Pentax has fixed anything.
Last I spoke to them they said a firmware update was due (that was a phone call in Jan) I don't think the last firmware did anything to address the problem so I would have to wonder if Pentax ever took the issue seriously.

[JimJohnson]

Mr Spocko, I see you are in England ... I suspect your AF issue isn't just 2700K - 3200K incandescent light, but also your country's 50Hz AC power. In both North America and Japan, the power grid operates at 60Hz. I'm sure the AF electronics use some kind of timing circuit to regulate data flow (all digital computing is based on clock pulses to keep data channels in sync).

If the camera's clock operates at some exact multiple of 50, the contrast of this color light in combination with a harmonic at which the light blinks, could very well confuse the camera's AF. If I were in Europe, I would at least do the following experiment- #1-set up a scene that shows the AF issue. #2- fine tune the AF for daylight conditions. #3- take another shot at the same identical scene/settings with the adjusted camera. Still out of focus? #4- place a high-contrast AF target in the scene. Still out of focus?

Now it gets tough, the final check is to use the same scene but with incandescent lighting running at 60Hz... any chance you or the camera could make a round trip to North America or Japan? I was in Germany last year, but won't likely visit another 50Hz country before 2013 or 2014.

The reason I say all this is because after fine-tuning my camera's AF, I just don't see this issue. And I have one of the little mini-studios for shooting small items for sale. It uses two incandescent lights in the spectrum you identified and I have no focus issues.

[Ray Pulley]

I'd wager Canon and Nikon are likely to be quite a bit better for AF all round, but don't take my word for it play with a few and enjoy accurate AF "most" of the time

Still kicking that same old dead horse Barry?

Just to add a little balance (and levity) to "Mr. Spocko's" comments, Barry (aka as Mr. Spocko) purchased a discontinued Nikon D90 instead of the D7000 due to the many problems that the D7000 has had, including AF problems.

Here is a Barry Spocko quote from the "other" forums where someone was asking about buying a D7000 given the number of reported problems with the D7000:

"So whilst I try to judge things on their own merits and ignore what could be some iffy ones rolling off the line or maybe user error. Sometimes problems do get blown out of proportion on forums. But there have been a few too many AF complaints about the D7000 to be comfortable buying one right now."

Ray