K20D Noise?

[Jewelltrail]

Wonders of modern production. Like anything you get sample variation... this is probably the real case here. Some K10's had a red one side, blue other side when dark exposures were push processed hard. The cause was never really found out. Seems the k20 has some models w/ at least the same tone l and r . You could get a better one next time.. 6400iso is really good for nothing but "need to get the shot".. certainly not quality... I doubt this is any different then any other brand w/ a possible exception of much more expensive cameras (w/ much more expensive parts)...
as much as it pains me to say this but this camera is not suitable for what you need. Maybe testing 10 others you can get a good one but...........
6400, 3200 you ALWAYS take your chances and it's best to push the initial exposure as far to the right as you can.
I don't know (or want to take the time to check) which of your samples is iso 1600. The one I looked at is 3200 and w/ a better exposure it isn't too bad though the blue l,r toning is there, but barely in the bright top and only creeping in in the shadow area. which may be normalish anyways (dumbbell picture w/ creme/beige carpet).
I don't understand why people think any of these cameras can produce gallery prints at such high iso's As the iso range goes up your dynamic range decreases significantly, and your noise increases.... it's the nature of the beast. There is good software to deal w/ some of these problems but there not in the camera so to speak.
Hint: If you need 1600 do your samples at 1600 not 3200 or 6400... then judge. Image quality starts to break down rapidly at these high iso's

I agree with what Jeff says. No matter what you opt to do with the K20--Most importantly, expose to the right.. Just compare #8 to #9 one more time--#9 so much better and #9 closer tot he right of the histogram--both shot @ 6400. Best!

[NeverSatisfied]

Originally Posted by Jewelltrail

I agree with what Jeff says. No matter what you opt to do with the K20--Most importantly, expose to the right.. Just compare #8 to #9 one more time--#9 so much better and #9 closer tot he right of the histogram--both shot @ 6400. Best!

Great advice! I don't do much with high ISOs, but I've had noticeable noise even at ISO 400 if underexposed. Yet in comparison, *properly* exposed shots at 1250 are clean as a whistle. Expose to the right, can't be stressed enough.

[Haakan]

Originally Posted by nicolaie

pentax has proven over time that they cant do in-camera processing, just can't.

I have a different opinion. I really like the way Pentax JPEG engine handles the noise. Compare thse two images taken at ISO 3200 (from Imaging Resource). First K20D then Nikon D300. In my opinion the way Pentax shows the texture is much more preferred than the smearing produced by the Nikon D300 JPEG engine. Of course you can shoot RAW and do better, but the point was to compare the JPEG engines.

Best regards,
Haakan

[nicolaie]

as always, i think it comes down to taste. i much prefere the natural, neutral "go anywhere" look of the D300 in this example. no drama, ISO3200, slightly soft, some luminance. the K20 shows texture, and a fare share of chroma. the shot looks busy, i don;t like this look, and i would loose some of that texture anyway (unintentionally) in my attempt to ease the noise.

[jeffkrol]

Originally Posted by nicolaie

as always, i think it comes down to taste. i much prefere the natural, neutral "go anywhere" look of the D300 in this example. no drama, ISO3200, slightly soft, some luminance. the K20 shows texture, and a fare share of chroma. the shot looks busy, i don;t like this look, and i would loose some of that texture anyway (unintentionally) in my attempt to ease the noise.

Guess it does depend. I like a jean shirt to look like a jean shirt not a sueded or velour shirt.
Of course if I want it to look like a velour shirt I (note I) can choose to do it.
Personally I'd shoot RAW and let me and a much more powerful suite of software decide..........
Of course some of the texture in the Pentax may be due strictly to noise or jpg artifacts... I prefer in-between I guess. AND RAW

10 min in Corel Photopaint

[Haakan]

Originally Posted by nicolaie

pentax has proven over time that they cant do in-camera processing, just can't.

Originally Posted by nicolaie

as always, i think it comes down to taste. i much prefere the natural, neutral "go anywhere" look of the D300 in this example. no drama, ISO3200, slightly soft, some luminance. the K20 shows texture, and a fare share of chroma. the shot looks busy, i don;t like this look, and i would loose some of that texture anyway (unintentionally) in my attempt to ease the noise.

Now that is better. Instead of a categorical statement of that Pentax "can not do" agreeing that is a actually matter of personal taste. With Pentax JPEG I feel have much more options, e.g. I can easily add some blurring in Photoshop and turn the jean shirt into velour, but the opposite is hard.

Best regards,
Haakan

[nicolaie]

Originally Posted by Haakan

Now that is better. Instead of a categorical statement of that Pentax "can not do" agreeing that is a actually matter of personal taste. With Pentax JPEG I feel have much more options, e.g. I can easily add some blurring in Photoshop and turn the jean shirt into velour, but the opposite is hard.

Best regards,
Haakan

well, i the truth is in between. let's remember that we are looking at a 100% crop out of 12-14 megapixels. resized to fit a computer screen it makes no difference, maybe the nikon shot looks more neutral, and the pentax shot more colorfull and slightly sharper/noisier.

secondly, those are 100% shots at iso3200. if you would try to remove the noise in the pentax shot in order to print larger-that-average you yould most likely end up with a velour as well.

i shoot raw as well, so the nikon shot would give me less headache. but this is just me.

cheers.

[jeffkrol]

Originally Posted by nicolaie

well, i the truth is in between. let's remember that we are looking at a 100% crop out of 12-14 megapixels. resized to fit a computer screen it makes no difference, maybe the nikon shot looks more neutral, and the pentax shot more colorfull and slightly sharper/noisier.

secondly, those are 100% shots at iso3200. if you would try to remove the noise in the pentax shot in order to print larger-that-average you yould most likely end up with a velour as well.

i shoot raw as well, so the nikon shot would give me less headache. but this is just me.

cheers.

see above, you can remove the noise enough w/ out flattening it enough..resharpen... you have to over-sharpen to print anyways (see Bruce Fraser).... and it's better. weather your printer picks up the detail (printers naturally soften images) is another story. In reality it may be closer then it looks but...???
Actually w/ the nikon shot it's just a matter of not knowing what you lost that saves time....

[Jewelltrail]

Okay, I took two quick HIGH ISO shots with the K20. The lens is my later model 67 (MF) 55m f4. There is no post processing whatsoever--I shot RAW and simply resampled down to forum restrictions. I could have ran this through my Neat Image Noise software, but did not. Please note how far to the right the histogram is! I realize these are small pics, but even @ full res the pics are surprisingly good.

The 1st shot: ISO 32000-wide open-incandescent light-1/50th

The 2nd shot: ISO 6400--wide open-incandescent light--1/100th

[Jewelltrail]

Okay here are the crops, not %100, but they give a good idea. I tried, but was unable to insert them into original pic post. First one is ISO 3200, if not obvious:

[Henkezd]

Thats how mine looks in the parts that doesn't get blue... To take such images wouldn't even be possible, even if I exposed like that I'm afriad.

The camera is at it second trip to the service center, trip number 5 in total, had an k10d that i got replaced earlier because they couldn't fix the AF, and the k20 I got is worse than the K10 that pentax took back, and is not helped by the AF adjustment feature.

I will report back when I get the camera back
Thx for all replies

[Jewelltrail]

Henkezd: I will report back when I get the camera back

Please do--with pics @ 3200 & 6400 and some big crops. It will be great to see your K20 doing what it is supposed to do! Best!

[res3567]

Originally Posted by Lance B

Excellent post.

I love this:
THEY DO NOT COME TO PENTAX TO RESEMBLE THE COMPETITION---THEY GREW OUT OF DOING THAT IN HIGH SCHOOL--THEY COME TO PENTAX TO DISTINGUISH THEMSELVES FROM THE COMPETITION

I agree! I think Im gone have to buy a K20D to compliment my excellent K10D to show the competition that Pentax can hold it's own and then some!

[octavmandru]

Is as Nicolaie said. Up to your taste.
I shot the same scenes once aside with one friend with a D90.
I like my pictures more and he likes his better. (well, he has no choice )

[RiceHigh]

And you're not very unlucky. The problem you've decribed had been reported earlier before:-

RiceHigh's Pentax Blog: Strange K20D Noise Patterns

And full and repeated tests had been carried out to nail the problem.

For more banding issues found and reported for the K20D, see the following:-

RiceHigh's Pentax Blog: Search results for K20D banding

Originally Posted by Henkezd

Hi, I got an K20D as an replacement for my K10D that pentax took back, the problem is that this new K20D I got works even worse than my old K10D

More about the other problems later, first of all, it makes images blue in the lower border on higher iso, depending on object it shows more or less.
To show this I made an video with some samples that I put up on youtube.

YouTube - Pentax K20D Noise

To make matters worse, it also front focuses some milimeters and behaves very wierd.
I sent it in for service some weeks ago and all I got was a paper with tips of settings like "Auto-ISO" which made me very angry beacause I have studied photography for 2 years and been photographing with d-slr´s for about 5 years, the only regret I have is that I chosed pentax over canon or nikon

So please Pentaxforums, is this a common experince of pentax or do I just have bad luck?
Sorry for my english btw, hope you understand me anyway

Best Regards Henrik