[canonfather]

In November of 2010 I noticed the PEF (RAW) files of my K200D were showing some very choppy digital artifacts – almost a posterization of the image. The artifacts were just as pronounced in the broad open areas of the images as they were along high contrast edges.

Searching for a solution I discovered the 1.01 firmware update at the Pentax site. I successfully installed it, and went happily on my way, shooting PEF files without the digital junk in them. I had no idea it could revert.

However, today, I happened to be looking at a PEF image at the 400% view on the Pentax Photo Viewer, and realized the very ugly artifacts had returned. I had no idea why. The camera still shows firmware update 1.01 is correctly installed.

I can only think of two possible explanations:
(1) At Christmas I got a 32 Gig class 6 SDHC card. Before then I had used 8 Gigs max, class 4. This would be my first guess.
(2) It also occurs to me that there is a slight chance the lower voltage output of NiMH batteries could cause some write issues to the card, although that is even less likely than the previous guess.

The k200e101w.exe download that created my firmware installation file was version 2.80.5.12 – it created the file fwdc184b.bin for the update – which gives me no indication of whether it is the 1.01.00.05 or the 1.01.00.06 update. The date for the file’s modification is 3-24-2010.

I just checked again on the Pentax website and it is still the same file version of k200e101w.exe being posted for the firmware update – version 2.80.5.12 (I just downloaded it to check). So I have no indication that there is any improved update available for my K200D.

I am wondering about the possible benefit of an attempted reinstalling the firmware update – except I’m quite concerned about disabling my K200D entirely. I’d just as soon keep shooing *.jpg files as shooting none at all.

Any thoughts are much appreciated.

[Adam]

I don't think you're going to gain much be reinstalling the same firmware.

Are you sure your raw processor isn't to blame?

[canonfather]

I suppose the only way to check on the RAW processor is to send the camera in ... and wait for an expensive quote for repairs.

[enoeske]

why don't you post one of these messed up pictures so we can dissect it

[Wheatfield]

Why are you looking at stuff at 400%?

[canonfather]

Thanks, Adam - I am with you 100% on the futility of an attempted reinstall of 1.01.

Thanks, enoeske - here are two images - shot with the K200D on RAW+ and then viewed with the Pentax Photo Browser - screen capture at the pixel level. I think the digital artifacts in the PEF file will be apparent - even though, in my ignorance, I've resorted to posting it on a compressed file host. This is the first thread I've ever started on PF

Wheatfield - I don't normally zoom past 100% unless I think I see something my aging eyes find disquieting, in which case I want to verify that the problem isn't just intraocular floaters (muscae volitantes).

K200D IMGP3078 PEF pixel level pictures from midwest photos on webshots (PEF file scrn cptr)
K200D IMGP3078 jpeg pixel level pictures from midwest photos on webshots (JPG file scrn cptr)

[enoeske]

Those look perfectly normal to me, even good, for 400%. You will likely see this effect when shooting high contract subjects like black on white.

[Ivan Glisin]

K200D IMGP3078 PEF pixel level pictures from midwest photos on webshots (PEF file scrn cptr)
K200D IMGP3078 jpeg pixel level pictures from midwest photos on webshots (JPG file scrn cptr)

Looks good to me too. Note that camera can pick up small variations in ink density and paper texture when shooting printed material. At 100% or 400% those should be visible, as in your case. So I'd say nothing is wrong with the camera.

[canonfather]

Thanks Ivan - et al. I am aware of the variations in the ink and paper media - my first observation of the digital artifacts was on a plastic ID card that had no grain or texture, so the printing was as crisp as a test pattern.

I think my biggest problem here is that I have overly high expectations of the RAW format, and the PEF format of RAW in particular.

Specifically, I keep forgetting to make allowances for things like:
(1) my computer only shows 8 bits of color depth, when the PEF files have 12.
(2) PEF (Pentax RAW) files DO employ some compression - I had not known or else forgot that. Compression of any kind naturally leads to digital artifacts, no matter how small.
(3) virtually all my files end up converted to jpg for actual viewing/printing - so they can never show all the information stored in the higher fidelity files.

Since I found the digital artifacts even in the best PEF files, I've tested using the DNG format instead for the RAW files, and that seems to produce a cleaner file, although I had to download a new converter to see them because the Pentax bundled Silky Pix wouldn't convert or view them.

Although the DNG files seem only have 8 bits of color depth, (maybe that's the fault of my conversion settings) they are still a larger file size than the PEF format RAW files and seem not to display the same degree of fragmenting/fracturing at the square corners of high contrast imaging.

My goal/hope in using the PEF to preserve all the color depth was to be able to extract more usable image information from the shadow areas, since I try to underexpose to prevent burnout and so achieve the greatest EV range in the final 8-bit JPG image. From what I've read about the JPG format, much of its compression is accomplished through limiting the color depth in the darker levels. But I don't think I want to sacrifice the clean-ness of the image to achieve the extra bit depth.

Thanks, everyone.

[Ivan Glisin]

(2) PEF (Pentax RAW) files DO employ some compression - I had not known or else forgot that. Compression of any kind naturally leads to digital artifacts, no matter how small.

Not in this case. RAW employs so called "lossless compression" that allows for the exact original to be restored. Some other commonly used compression formats are also lossless, such as ZIP or GIF.

This is in contrast to "lossy compression" where the exact original can not be restored, instead just an approximation of the original data is made. Most commonly known examples are JPEG and MP3.

So artifacts you are seeing are not due to compression.

(3) virtually all my files end up converted to jpg for actual viewing/printing - so they can never show all the information stored in the higher fidelity files.

That's true. Try saving with best JPEG quality (12 in Photoshop, but commonly 10) or save in TIFF and examine at this level. Still, I am expecting you to see similar artifacts as a consequence of some noise present at any ISO.

Although the DNG files seem only have 8 bits of color depth, (maybe that's the fault of my conversion settings)

It probably is due to settings. It should be 16-bit, and keep it that way.

Bottom line, I think you are scrutinizing test images too much. You are not experiencing any problems with your camera, sample images look exactly as they should. Perhaps K200D sensor could be tricky to handle at times (I have K10D, same sensor) so just make sure you shoot at ISO 100 for best results, K10D/K200D are simply not that great at high ISO.

Concentrate on what quality you can get for intended final output (usually web JPEG or print on paper) and forget about 100% or 400% examinations.

[TOUGEFC]

Correct me if I'm wrong, but I'm pretty sure that the k200d firmware 1.01 update is only to improve sd card compatiability.

[Haakan]

Have you tried to open the RAW files in another tool than the Pentax Photo Viewer?. It could perhaps be the RAW conversion in the viewer that provides the artifacts you see.

Best regards,
Haakan

[cats_five]

<snip>
(1) my computer only shows 8 bits of color depth, when the PEF files have 12.
(2) PEF (Pentax RAW) files DO employ some compression - I had not known or else forgot that. Compression of any kind naturally leads to digital artifacts, no matter how small.
(3) virtually all my files end up converted to jpg for actual viewing/printing - so they can never show all the information stored in the higher fidelity files.

What software are you using? Photoshop PSD files can have 16-bit colour depth. There are also no problems printing PSD files.

What monitor are you using? A calibrated wide-gamut monitor (IPS panel) makes a huge difference to how images look.

If you *do* have to convert to JPG then do a really good-quality conversion. How exactly you do that depends of course on the software you are using.

[enoeske]

That is the best firmware at this point and you wouldn't want to do anything with that. Mess with it, and you would get your PSP bricked. Believe me, that is not good.

But the best thing on PSP would definitely be a PSP Go. Get PSP Go's firmware by the time it officially launched on October. In the mean time, get the unreleased-yet PSP Go while it's free.

wrong...uh...forum?

[ytterbium]

Can you post more detailed example?

E.g. crops with:
-RAW screenshot where posterization dosnt happen,
-RAW screenshot with posterization,
-JPEG wit the SAME image (shot in RAW+JPEG mode), showing no posterization.

Otherwise i cant understand where the problem is. The posted images seem perfectly fine to me.

I can only speculate that you're referring to some sort of sharpening artifacts, caused by RAW software settings and low in-camera JPEG sharpening setting (thats why the difference). Might as well be related to demosaicing algorithm used in raw software and Bayer artifacts:
http://www.rawtherapee.com/RAW_Compare/
But i don't see that either in example you posted.