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05-11-2008, 12:48 PM   #76
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QuoteOriginally posted by jgredline Quote
Hey Chris, I found a ''hot pixel'' problem with my ''K1OOO.''

Here is the proof.


On a more serious note, I just spend the last 1/2 hour pixel peeping and I see no such issue with my K20D, In fact, after all the cropping and looking at these 100% crops, I am even more impressed by the K20D.
I thought that was going the be a picture of a "hot bird"

05-11-2008, 12:58 PM   #77
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Funny stuff guys!

The problem here is though that I still don't have an image on my desktop with this hot pixel issue... I'm still waiting for confirmation from the one image because it was heavily edited and want the real deal, but with all these people having hot pixel issues why don't I have tons of pictures to weed through?

I've abused my K20D all day now and I still don't have a hot pixel to show up, not even on the screen and yes I'm using live view.

Phil show me your proof!
05-11-2008, 01:07 PM   #78
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Hello,

I looked through all my long exposure pictures looking for hot pixels. I already claimed I had hot pixels on DPR, but actually they were caused by the software used for making HDR pictures (they were in the final HDR picture, not in the originals).

http://adal.ro/temp/k20d/IMGP2432.JPG - 2 sec, ISO 800, F5.6, kit lens

9 hot pixels: 1 green near 2 red, 2 blue, 1 green, 1 green, 2 green

There were 17 pictures in this series, all shot at night with little light and exposures from 0.5 to 10 sec. This was one of the last pictures, shoot a minute after a 10 sec one. Two pictures made afterward, a 3 sec and a 10 sec don't have any hot pixels. LiveView was not used at all.

The picture is blurred because it was hand-held against a door frame.

BTW, I love the camera and this is a non-issue for me.
05-11-2008, 01:18 PM   #79
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QuoteOriginally posted by adal Quote
Hello,

I looked through all my long exposure pictures looking for hot pixels. I already claimed I had hot pixels on DPR, but actually they were caused by the software used for making HDR pictures (they were in the final HDR picture, not in the originals).

http://adal.ro/temp/k20d/IMGP2432.JPG - 2 sec, ISO 800, F5.6, kit lens

9 hot pixels: 1 green near 2 red, 2 blue, 1 green, 1 green, 2 green

There were 17 pictures in this series, all shot at night with little light and exposures from 0.5 to 10 sec. This was one of the last pictures, shoot a minute after a 10 sec one. Two pictures made afterward, a 3 sec and a 10 sec don't have any hot pixels. LiveView was not used at all.

The picture is blurred because it was hand-held against a door frame.

BTW, I love the camera and this is a non-issue for me.
Sweet, I now have one image with true hot pixels! Awesome!

EXIF is perfect and I'll work on confirming it and send this one to the Pentax crew on Monday.

05-11-2008, 01:54 PM   #80
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coming to think of it a hot pixel would not be white because that would mean that all four photosensors in that pixel would have to be faulty and that would be very unlikely
05-11-2008, 02:11 PM   #81
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I have now confirmed m first source image and after one pixel mapping attempt all the hot pixels are gone!

Such a hug development and one confirmed image with the fix actually doing what it's supposed to do. Thought DPR said the pixel mapping wouldn't work
05-11-2008, 02:21 PM   #82
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QuoteOriginally posted by codiac2600 Quote
Such a hug development and one confirmed image with the fix actually doing what it's supposed to do. Thought DPR said the pixel mapping wouldn't work
As I understand it, DPR said that it would be inappropriate for them to discuss the issue until they'd gotten the problem worked out with Pentax, but did refer to another thread where someone pointed to the Polish site review, which did say that. But I'm not sure how in depth they actually read the other review or were just aware of it as a report of a similar problem.

My money is still on "raw converter bug", but we'll see.
05-11-2008, 02:49 PM   #83
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USe the ignore function?

QuoteOriginally posted by jgredline Quote
I agree with this. Further more, I suggest that a poll be started and let the members decide weather or not Rice high should be banned...
If enough members just use the ignore function Adam won't have to do the deed.

05-11-2008, 02:55 PM   #84
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QuoteOriginally posted by codiac2600 Quote
I have now confirmed m first source image and after one pixel mapping attempt all the hot pixels are gone!

Such a hug development and one confirmed image with the fix actually doing what it's supposed to do. Thought DPR said the pixel mapping wouldn't work
My understanding is that the problem isn't that there are hot pixels (they are a fact of life), but that they won't sit still. Mobile hot pixels are, apparently, a very bad thing, as it renders pixel mapping useless.

Last edited by Wheatfield; 05-11-2008 at 07:58 PM.
05-11-2008, 03:07 PM   #85
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I also have a K20d with no hot pixels (as far as I know). Maybe I will play around with weird edge-case tests to try to expose them if i have some time. Just curious though, what would dpreview have to gain by lying about it? My guess is that they have found something that may not be evidient in regular shooting, which would make sense for them to really be "pixel peeping" - they ARE trying to write a technical review.

Also, I'm not the biggest fan of RiceHigh, the way he goes about saying things can be pretty hard to take, but i don't think he should be banned. He generally is talking about real issues, even if he likes to sensationalize them (Maybe he can apply for a job at Fox News?). I don't think what he does is any better or worse than the hordes of people denying that the issues he talks about exist at all. If we aren't going to have a middle ground, maybe the best we an do is two polarized sides to the "discussions"

I do agree though, that it's pretty strange how dedicated he is to seeking out any and all Pentax-related issues, and blowing them up to epic proportions, even when they are minor and/or very uncommon. Very strange dude. Must take a lot of energy! He must not get a lot of actual shooting done

Anyway, I'm very happy with my K20 and lenses, so I'm going to go take some pictures!

Last edited by ennoia; 05-11-2008 at 03:43 PM.
05-11-2008, 03:28 PM   #86
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Facts added

I think it is time now we are adding some facts to this thread

@Codiac, BTW, can you possibly close my thread on the issue? It is now superseeded by yours.


Ok, I had reported that I don't have the issue myself and I continue to do so. However, I have now done a more thorough test which may help others and this thread to progress

Test procedure (with my own K20D):
  • Run LiveView for 10 minutes (you have to reengage it in between)
  • Take a number of shots out of LiveView (mine were taken at f/2.8 with a DA40 in low light, but it doesn't matter, of course) Make sure you get enough dark areas.
  • Use ISO100 and 1/15s or faster (and make sure Long Exposure Noise Reduction is Auto (not On) -- this is the default).
  • Shoot in RAW (PEF)
  • Load into PhotoMatix Pro (there is a free demo which does fine here -- it loads K20D PEFs) and stay in the preview view
  • Magnify and increase brightness in preview view for extra information.

As a matter of fact, In-Camera JPEGs, ACR, Lightroom and Pentax Photo Browser/Lab all map out hot pixels -- as does PhotoMatix in its rendering stage. This may explain my procedure.

My findings:
  • Camera gets noticeably warm on the back
  • I got 2 hot pixels (1 red, 1 blue) but at constant location and in all images, also before using LiveView. Easily mapped out. Fully ok.
  • When I "go into the noise" (PhotoMatix does it easily for you thinking it is an HDR image ) you may observe a few extra, dimmer hot pixels, about 6 extra or so.
  • In this "into the nosie" mode, I indeed saw a white hot pixel, or two. But not very bright, actually. Nothing to worry about and again, stationary before and within LiveView.

I attach screenshots from PhotoMatix because one cannot store the preview and the final result doesn't seem to have any hot pixels anymore ...

Summary:
  • LiveView creates heat, but no hot pixels (for me)
  • There are hot pixels, exactly as many as with any other manufacturer
  • I've seen 1 or 2 of those white hot pixels, which point to a firmware problem.
  • I've seen nothing close to the Polish images.

Attachments (changed into gallery links):
  1. Full frame (The hard contrast is PhotoMatix' preview -- looks ok in LR).
  2. Crop after LiveView (containing the 1 blue of 2 overall hot pixels)
  3. Crop after LiewView with ISO100 noise pushed up to reveal some extra (dim) hot pixels, including a white one.



Last edited by falconeye; 05-11-2008 at 04:12 PM. Reason: Changed attachments to gallery links because attachments got reencoded and lost their hot pixels ...
05-11-2008, 04:05 PM   #87
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I want to say some final things on this Hot Pixel stuff. I do not know if my camera had hot pixels or not. I do know I had foreign white particles (dots) on long exposure (3-8 seconds) shots. I also know that after using the “Pixel Mapping” feature on my K20, I can no longer duplicate those white spots. I could not be happier. My thanks go out to everyone who reached out to help me with some of these new (to me) issues.

Best Regards,

Ernest
05-11-2008, 09:25 PM   #88
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Ok, so what is the best way to induce the dreaded hot pixel issue and should it be RAW or jpeg? As far as I know, whether it be RAW or jpeg, software automatically removes them either in the camera or in post process.

It looks like we will have to work very hard to try to induce this dreaded phenomenon. Maybe we should have classes so as we can teach people to be able to induce them at will.
05-12-2008, 05:24 AM   #89
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Classes. What a great idea! We need to exploit this camera specialty to the max. Will be able to convince the Rebelists that they need it on their camera. Its an electronic version of the Cokin "snowball in hell" filter.
thanks
barondla
05-12-2008, 05:41 AM   #90
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QuoteOriginally posted by Lance B Quote
Maybe we should have classes so as we can teach people to be able to induce them at will.
Lance, if you accept the pain to read my post just 2 above yours, you find your answers, in the section starting with "Test procedure".

However, if you didn't notice it, I am asking myself why I spent the work preparing my posting
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