[benjikan]

To show all of you my objectivity even in being a Pentax sponsor, I wish to share a problem I had with my K10D with the 21mm and 16-45 lenses. Now I am not yet sure what the exact anomaly is but when I would focus on the model's face, her face was slightly out and her feet tack sharp...I freaked. I initially thought it was my 21mm, but further observation showed the same problem with the 16-45. It may be that one of the camera's were off and as I have two bodies I'm not yet sure which it is. None the less, the whole kit is going back to Pentax to be critically bench tested. I had a similar problem with my 20D and my 50mm lens. The problem here is the fact that I am focussing on a vertical extreme, i.e the face and getting the opposite of my intended image. I only noticed this when I really got down to editing today. I will test both bodies with both lenses and get back to you with the results. I hope it isn't going to require a firmware update...

[carpents]

You might want to try this out:
self focus adjust: Pentax SLR Talk Forum: Digital Photography Review

[davemdsn]

I know that there have been scattered reports of some of the K10 bodies having focus issues. A critical bench test should have them in fine shape when you get them back.

[Tom Brown]

I can't help with your problem and certainly hope you get it resolved quickly.

I apologize for hijacking your thread but I am keenly interested in a comparison of the 21mm limited pancake to the 16-45mm. You have said much good about the 16-45 and have posted some spectacular pictures.

I have the 18-55mm kit lens and use it almost exclusively at the wide end. Actually, I find that it's sufficiently decent but I'd like something that's really sharp for a walking around lens. I could easily give up zoom for a tiny bit of extra sharpness.

Any advice for someone who doesn't have access to this equipment to test for myself?

[WMBP]

To show all of you my objectivity even in being a Pentax sponsor, I wish to share a problem I had with my K10D with the 21mm and 16-45 lenses. Now I am not yet sure what the exact anomaly is but when I would focus on the model's face, her face was slightly out and her feet tack sharp.

Is that what is called front focus?

Will

[Denis]

To show all of you my objectivity even in being a Pentax sponsor, I wish to share a problem I had with my K10D with the 21mm and 16-45 lenses. Now I am not yet sure what the exact anomaly is but when I would focus on the model's face, her face was slightly out and her feet tack sharp...I freaked. I initially thought it was my 21mm, but further observation showed the same problem with the 16-45. It may be that one of the camera's were off and as I have two bodies I'm not yet sure which it is. None the less, the whole kit is going back to Pentax to be critically bench tested. I had a similar problem with my 20D and my 50mm lens. The problem here is the fact that I am focussing on a vertical extreme, i.e the face and getting the opposite of my intended image. I only noticed this when I really got down to editing today. I will test both bodies with both lenses and get back to you with the results. I hope it isn't going to require a firmware update...

Was the focus selection on Auto, Sel or spot. I have 16-45 and would like to make sure I don't have the same issue. My test photo so far were with spot and appear sharp at 26mm and up. A little soft on the edge closer to 16mm.

[benjikan]

Was the focus selection on Auto, Sel or spot. I have 16-45 and would like to make sure I don't have the same issue. My test photo so far were with spot and appear sharp at 26mm and up. A little soft on the edge closer to 16mm.

I first marked camera 1 and 2. I was shooting in manual mode with flash and used select focus. Why? As I stated in an earlier post, I rarely am shooting parallel to the model. I am often on the floor shooting up and if I use the centre focus, by the time I re-frame, the parallax is way off. One of the K10D's is more off than the other. I am still not sure if it is the K10D or the lenses. One thing I do know is that one of the bodies No.1 produced superior results. I spoke with Pentax and told them that I wasn't in to having to manually focus. When doing so the results were spectacular with the 21mm. I really don't have the time to focus manually when shooting. They are sending a messenger on Monday to pick up all my stuff. They will bench test and tweak all the lenses for me...I hope they understand that it is on the vertical horizon that concerns me. I don't want to go to a shoot with apprehension about whether or not my images will be in focus. That should be a given. The 40 and 70 were absolutely perfect. The weird thing is this. Imagine you are lying on the floor shooting up at the model. You double and often triple your auto focus confirmation. You get on to the big screen to make your selects and the feet are tack sharp and the face is out. Not so badly that I can't go to press but...I focussed on the eyes at about a 35 degree angle to her face. The feet should be out, not the face. I was shooting at about f 9.0 at 100 iso...Here are one of the culprits...

---

Last edited by benjikan; 03-15-2007 at 09:49 AM.

[benjikan]

Is that what is called front focus?

Will

Big Time..I wish I could download the test I just did on books between the two bodies and the 21mm. The weird thing is that when I was certain that Camera 1 was the good one, I started to shoot tons of images of defined sharp edged objects, i.e. books, CD's, DVD's etc.....Same problem...S--T, I am perplexed.

Oh well. Don't have another shoot of consequence till the end of next week. I hope they are repaired in time. I will be functioning as a Consulting Creative Director at Publicis on a one shot project in the mean time...

[benjikan]

You might want to try this out:
self focus adjust: Pentax SLR Talk Forum: Digital Photography Review

I'll let Pentax do it for me...

[benjikan]

To show all of you my objectivity even in being a Pentax sponsor, I wish to share a problem I had with my K10D with the 21mm and 16-45 lenses. Now I am not yet sure what the exact anomaly is but when I would focus on the model's face, her face was slightly out and her feet tack sharp...I freaked. I initially thought it was my 21mm, but further observation showed the same problem with the 16-45. It may be that one of the camera's were off and as I have two bodies I'm not yet sure which it is. None the less, the whole kit is going back to Pentax to be critically bench tested. I had a similar problem with my 20D and my 50mm lens. The problem here is the fact that I am focussing on a vertical extreme, i.e the face and getting the opposite of my intended image. I only noticed this when I really got down to editing today. I will test both bodies with both lenses and get back to you with the results. I hope it isn't going to require a firmware update...

Just tested the 12-24..It is TAC sharp...

[benjikan]

I can't help with your problem and certainly hope you get it resolved quickly.

I apologize for hijacking your thread but I am keenly interested in a comparison of the 21mm limited pancake to the 16-45mm. You have said much good about the 16-45 and have posted some spectacular pictures.

I have the 18-55mm kit lens and use it almost exclusively at the wide end. Actually, I find that it's sufficiently decent but I'd like something that's really sharp for a walking around lens. I could easily give up zoom for a tiny bit of extra sharpness.

Any advice for someone who doesn't have access to this equipment to test for myself?

What I would suggest, is take the K10D body to a store and test it with the 16-45. It can be very critically sharp. Just make sure that you have an opportunity to magnify the image sufficiently to scrutinise the image. Great lens, even wide open.

[JJJPhoto]

Ben,

This is sounds like something I've noticed with one of my K10D bodies and with my DL (shooting with the FA 50 1.4 and a Sigma 24-70 2.8).

The most recent example was shooting a headshot for a model's portfolio last week where I was close and focusing on the model's eyes at f2.8 with the FA50. I focused on the model's eye and took a shot ... the eye looked completely out of focus even though the K10D's AF indicator said the focus was locked. The model was seated and did NOT move ... especially not enough to cause the eye to be THAT out of focus. I refocused (same position, no camera movement) and took another shot. This time the eye was tack sharp.

I don't know what the heck caused that to happen. I've had a couple of similar things happen with the DL last year with the Sigma 24-70 2.8 DG but didn't think too much of it at the time because I though it might be a problem with the lens or just a weird issue with the budget-built DL.

Overall, I'm still VERY happy with Pentax, but I don't think the type of "focus variation" you and I are describing is just user error ... though I admit I'm NOT perfect.

[*isteve]

To show all of you my objectivity even in being a Pentax sponsor, I wish to share a problem I had with my K10D with the 21mm and 16-45 lenses. Now I am not yet sure what the exact anomaly is but when I would focus on the model's face, her face was slightly out and her feet tack sharp...I freaked. I initially thought it was my 21mm, but further observation showed the same problem with the 16-45. It may be that one of the camera's were off and as I have two bodies I'm not yet sure which it is. None the less, the whole kit is going back to Pentax to be critically bench tested. I had a similar problem with my 20D and my 50mm lens. The problem here is the fact that I am focussing on a vertical extreme, i.e the face and getting the opposite of my intended image. I only noticed this when I really got down to editing today. I will test both bodies with both lenses and get back to you with the results. I hope it isn't going to require a firmware update...

Others have reported problems with the 21. The 16-45 also seems to have its QC issues. If the other lenses work, I suspect the lenses need recalibrating not the camera.

[frank]

I heard that among all the 11 focusing points, only the center one is for F2.8 while the others only at F5.6 level (which means you might be off if a bigger aperture is used when focusing at that point).

I tested my K100D w/ a 77 lens, the center focusing point is spot on even wide open. But the vertical top focusing point is way off, the bottom one is okay, not as good as the center one, but is okay. To get around, I have to rotate the camera the other way around so I can use the vertical bottom (now it's the top) focusing point when I need to. As long as I know the problem, I can still get good enough results.

Maybe some K10D have the same problem?

[mutley]

To show all of you my objectivity even in being a Pentax sponsor, I wish to share a problem I had with my K10D with the 21mm and 16-45 lenses. Now I am not yet sure what the exact anomaly is but when I would focus on the model's face, her face was slightly out and her feet tack sharp...I freaked. I hope it isn't going to require a firmware update...

Front Focus/Back Focus has been a bit of an issue, but with you having a problem with it means it will actually be paid attention to and solved. This is at least one good thing.

If a firmware update is needed for this (which I doubt), now they will actually do it, unlike when we call Pentax.

Same thing with the high iso streaking pattern noise in shadows, or needing better quality, sharper jpgs. Luckily for you, these haven't become an issue, so even though they are substantial issues for many, Pentax will probably ignore them. (I bet when you mentioned these, the verbal reaction was dismissal, right?)

I surely don't wish these issues on you, and your shooting style doesn't call for high ISO, plus you shoot only RAW, but if these things jeapordized a shoot, Pentax would smack solutions into a firmware update so fast it would make your head spin.

As it stands, I've pushed these issues enough, and have given up. In all the hundreds of posts by owners on these subjects, Pentax has not acknowledged or given a reaction to ANYONE.

I'm going to wait to see what gets introduced in the March PMA. You would know better than us, but hopefully it won't be a K10DS, or K10D-2 where all these issues are solved, and even a 16 bit RAW file option is included - but the current regular K10D is discontinued with no further firmware updates. That would suck.

Larry