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Old Jul 12, 2009, 8:42 AM   #11
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bahadir - I think the difference was the fact that the K20 was inconsistent with stop-down metering and manual lenses - the K20's picture is less exposed than the K-7. It was fair with this lens but horrible with the SMC 24mm 2.8. Better than the K10, but not by all that much. These were both f22 - both cameras underexposed at f32, the K-7 more than the K20. Other than that, all of the K-7 pictures looked exactly alike (other than the change in DOF).
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Old Jul 12, 2009, 1:29 PM   #12
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It wouldn't surprise me if the video mode could only be used for a short time before ruining the sensor.

The live mode on the K20D is only for a short time to avoid sensor damage.
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Old Jul 12, 2009, 3:56 PM   #13
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Thanks, Harriet. Even though at this time I have no interest in the K7 having just bought the K20, it's nice to hear a review from someone I know and respect.

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Old Jul 12, 2009, 6:08 PM   #14
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Well, I couldn't reproduce the fault I had yesterday, so I'm pretty sure the problem is not strictly heat related. I'm going to contact Pentax tomorrow and see what they say.

Here's what happened to me - I tried live view for a picture I was taking (gotta read more about it - what I tried didn't work the way I expected it to). Then a few minutes later I decided to try the movie mode on some flags (there's a bunch of settings that I should have changed to make that work better). They were both really short (under 20 sec.). Then I started taking regular pictures again, and a line that's a little lighter, and somewhat green appeared right in the middle of the picture, going from top to bottom (when shooting landscape). It was in all of the other pictures I took at the park.

I ended up downloading exiftools last night and finally figured out how to give a command in unix. People think that it's heat related, but after today I know that's not the whole story. The picture I took before the movie showed 34 C, the first one that showed the line was at 36 C. The last one I took at the park, which also showed the line, but it looked like it was fading, was 35 C.

Today I went for a hike (not much for miles, but it took several hours because I kept stopping to take pictures and play with the camera). Not one line on any of them, and when I checked the temperatures of each shot, some were 41 C, and most over 34 C. Not surprising since the air temperature was in the 90's F (or above 32 C) for the last part of the hike. So it's something connected with live view and video recording more than just heat by itself. In some ways, it's a non-issue for me as I don't use either one much and don't expect to. On the other hand, I want to get it fixed.

On one of the other boards, someone said that the first shipment of sensors from Samsung were faulty. I don't think anyone really knows at this point, other than to know that not all cameras show this - there are lots of people who are taking lots of video and using live view and not having a problem.

P.S. Here's an example, 100% crop, I adjusted things a bit to make it more obvious:



The first picture where the line first showed up is at: http://mtngal.zenfolio.com/img/v4/p330224992.jpg - this is the full sized, straight from the camera jpg file. I was shooting raw+ and the line shows up in both.

Last edited by mtngal; Jul 12, 2009 at 6:17 PM. Reason: added example
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Old Jul 12, 2009, 10:07 PM   #15
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That's enough to make me want to wait a few months to get the worms out of that puppy. And I have to question what appears to be noise in the background area (on the stem and elsewhere). How would the K20D treat that with the same lens and settings? Would a different setting either in-camera or post-processing resolve the background smoothness?

Thank you for taking time to review and post.

Last edited by gfmucci; Jul 12, 2009 at 10:10 PM.
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Old Jul 12, 2009, 10:25 PM   #16
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I think the K20 would have been very similar - the link to the last picture (I assume that's the one that you are asking about) was on the K-7's extended dynamic range setting. They've got two different options - one is highlight compensation and one shadow compensation. Since I was having some trouble with highlights getting blown out, I was experimenting with the highlight compensation. The K20's extended dynamic range would have introduced more noise, I think (I never liked it). I was expecting (hoping) that the K-7 wouldn't introduce noise for the highlight compensation, but it does. Off the top of my head, I think it is better than how I remembered the K20 to be, but it's been a long time, so I don't really know. I ended up turning it off when I saw this set of pictures.
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Old Jul 13, 2009, 12:37 PM   #17
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Very nice post mtngal, i don't know what to think as of yet about the K-7 i hear great things and i hear not so great which is making me dizzy.
I have sold my k20D and am concidering on buying the K-7 but i think i should hold off till at least i read reviews from dpreview, dcresource, or steves, but from what i have seen and k-7 testers on pentax forums the camera can't be beat, i have also seen high ISO 3200 shots that are usable
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Old Jul 13, 2009, 12:47 PM   #18
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Quote:
Originally Posted by mtngal View Post
Well, I couldn't reproduce the fault I had yesterday, so I'm pretty sure the problem is not strictly heat related. I'm going to contact Pentax tomorrow and see what they say....
That looks like a defective sensor. I've seen that exact problem before in other cameras and can remember seeing a technical explanation for what causes it (although it escapes my memory right this minute).

I'd see if your vendor will replace it for you if you just bought it.
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Old Jul 13, 2009, 3:06 PM   #19
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I talked to both Pentax and Amazon today. Both are happy to deal with my problem - Amazon will replace it and Pentax will repair it, my choice. I hate choices - I can either get another camera that may or may not have the same problem, or I can have a repaired (or possibly replaced) camera. I can live without a second camera body for the time it takes for the repair as I'm keeping the K20. I must say I was really impressed with Amazon, when I explained that I was leaning toward sending it back to Pentax first, but that the repair would take longer than 30 days, they offered to annotate my file/account that I could still return it if Pentax didn't repair it to my satisfaction and it was beyond the regular 30 days. I ended up deciding to follow my husband's suggestion - I'll return it to Amazon now and if the second one has the same problem, if so, I'll send it in for repair. If it doesn't, then I'll have a new, correctly working camera that much sooner.

JimC - Your comment goes along with the comments that were on another Pentax board - that Samsung's first batch of sensors has turned out to be defective (I'm not the only one who's had the same problem) and that Amazon got a bunch of them. Hopefully, Amazon will ship me one from a different batch, I hope that Pentax has had enough time to identify the serials numbers that would have been affected and notified Amazon which ones to return/not sell.
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Old Jul 13, 2009, 5:22 PM   #20
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Very nice review and write up. Sorry to hear about your K-7. I just got my K20 last week (surprise "update" gift from my lovely bride of 42 years), and it is quite a camera, as you well know. I'm "upgrading" from the K100D.

In looking at your exif, I do have 1 question. I notice that you have your name in the data. Can you share with me please how to do this? Thanks in advance.

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