Unscientific K-7 ISO testing

JohnBee · 01-12-2010, 02:37 AM

I woundn't know where to begin with a response tbh.

pcarfan · 01-12-2010, 07:18 AM

Originally posted by JohnBee

PS. on the other hand, I was not able to the original images, do you have a link? Perhaps it's time to get my glasses changes

The original images were posted in another thread...

FULL res 6400 (So a very large file)
Flickr Photo Download: FULL RES (3 of 3)

FULL res 3200 (So a very large file)
Flickr Photo Download: FULL RES (2 of 3)

FULL res 1600 (large file)

Flickr Photo Download: FULL RES (1 of 3)

P.S: John, that image you posted was absolutely fabulous irrelevant to what iso was used.

pcarfan · 01-12-2010, 07:23 AM

Originally posted by Laurentiu Cristofor

What I see in that area looks more like JPEG compression artifacts............If pcarfan's files are scaled down and compressed, what we might be seeing here are just side-effects of the algorithms used for scaling down and compressing the images. I've looked at his 3200 shot in original size and banding isn't half as obvious as it is in his OP.

I opened the same image in Rawtherapee ( to rule out LR causing it) and then exported to photoshop and saw the banding when viewed there and thus assumed it is neither the raw program nor the jpeg compression. So, I re-did the test now, but paid more careful attention to the image in rawtherapee before exporting and the banding is much less.

Here is the screen capture. I think there is less banding there, but there is still some.

The same image posted before (opened in LR and saved as Jpeg)

asdf · 01-12-2010, 07:39 AM

Originally posted by pcarfan

I opened the same image in Rawtherapee ( to rule out LR causing it) and then exported to photoshop and saw the banding when viewed there and thus assumed it is neither the raw program nor the jpeg compression. So, I re-did the test now, but paid more careful attention to the image in rawtherapee before exporting and the banding is much less.

Here is the screen capture. I think there is less banding there, but there is still some.

BTW, this is a picture-peeping problem not a pixel peeping one. You can see the horizontal pattern when you look at the entire picture. The horizontal discolorations become less distinct when you zoom in. If you can make a printout on a dye-sub printer, tell us if it looks better or worse.

pcarfan · 01-12-2010, 07:48 AM

I checked with some other images, opened in RawTherapee , and the banding is there with the more recent images. So, I am fairly certain it's not the Raw converter nor the jpeg compression.

asdf · 01-12-2010, 07:54 AM

Originally posted by pcarfan

I checked with some other images, opened in RawTherapee , and the banding is there with the more recent images. So, I am fairly certain it's not the Raw converter nor the jpeg compression.

Yeah, I see the pattern in the camera preview even. For others, who haven't noticed this, all you have to do to replicate this is to crank ISO to the max and shoot a uniformly black surface (or any composition with a uniformly black surface).

Mr.Turnip · 01-12-2010, 08:49 AM

Originally posted by Igilligan

Dang I really got to read this manual. You mean I can change metering between spot center matrix with the info / thumbwheel? I have been bangin back and forth thru the darn menu. A real pain...

YEP THERE IT IS

Thank you Claus >>> I really have to read the manual!!!

Hahaha what an idiot I am

Next time I am giving any advice or giving anyone any grief... Please link to this post!

LOOOL

- no problem..glad you found out

I didn't read the manual either, I just pushed all the buttons I could

...but I'm glad I did discover it...it's a pretty neat feature

SergioFromSF · 01-12-2010, 10:05 AM

Yes, great image! I too would love to learn to take and pp such an image quality.

pcarfan · 01-12-2010, 01:19 PM

Yeah! JohnBee I hope you will come through with those steps. In my monitor, the faces of the two girls towards the left end seem to have a bit more 'burning' than the rest, but otherwise that image was absolutely awesome.

JohnBee · 01-12-2010, 01:46 PM

Originally posted by pcarfan

Yeah! JohnBee I hope you will come through with those steps. In my monitor, the faces of the two girls towards the left end seem to have a bit more 'burning' than the rest, but otherwise that image was absolutely awesome.

Thanks everyone for your kind comments.
I'll look into putting together a walkthrough of the steps I used for that image.

Laurentiu Cristofor · 01-13-2010, 02:12 AM

Originally posted by JohnBee

Having said that... the banding is well and accounted for in all three images at 100% as well as the resized ones.

It's obvious to me in the resized 6400 image. But I don't notice it in the other images - not as obvious as that 6400 or dpreview's images, anyway.

Originally posted by pcarfan

I opened the same image in Rawtherapee ( to rule out LR causing it) and then exported to photoshop and saw the banding when viewed there and thus assumed it is neither the raw program nor the jpeg compression. So, I re-did the test now, but paid more careful attention to the image in rawtherapee before exporting and the banding is much less.

Here is the screen capture. I think there is less banding there, but there is still some.
<image removed from quote to save space>
The same image posted before (opened in LR and saved as Jpeg)
<image removed from quote to save space>

I can definitely see banding in the original image, although it's not obvious to me when looking at the original size. The new capture looks much better to me - if there's banding in it, it's below what I'd notice. I don't know what to say. I only use the Pentax software for conversion - I never used LR. I did use RawTherapee a few times to see if I can get better raw processing from it and what I noticed was that:
a) Pentax software was still better
b) when examining images at 100%, RawTherapee ones looked as if they were painted with a brush - I assume their algorithms are much more different than the Pentax ones.

Originally posted by asdf

Yeah, I see the pattern in the camera preview even. For others, who haven't noticed this, all you have to do to replicate this is to crank ISO to the max and shoot a uniformly black surface (or any composition with a uniformly black surface).

Tried that and it doesn't work to me - not in preview, not at 100%. Could it just be a problem with some cameras, or could it be that it requires the sensor to be used a lot before this starts showing up, or could it be interference from some other electronic device?

Igilligan · 01-13-2010, 02:21 AM

Do you have battery grips on your cameras?

pcarfan · 01-13-2010, 04:01 AM

Originally posted by Igilligan

Do you have battery grips on your cameras?

No, I don't. I am fairly convinced it is the firmware update that also included the FineSharpness2 settings, and I need to find out how I can get back to the original firmware. Any ideas?

P.S: I went ahead and ordered the DA15 yesterday, couldn't resist the small packaging

Igilligan · 01-13-2010, 10:20 AM

I can't remember seeing any Retro firmware threads. Good luck with that search.

Are you getting the horz banding in all your ISO 3200> shots? I did not think it was that bad in the test shots you posted here. I guess it is like PF... once you see it you cant help but see it. I shot the Tammy 70-300 for a month before someone started talking about PF in one of my bird shots. After that... it was everywhere. If I did that to you on this K20/k7 banding, I am truly sorry. From my point of view it was never really an issue for me.

On my k20 I would see it worse in some scenes and not at all in others. There seemed to be no real consisistancy in what caused it. Sometimes it showed up in darker parts of the scenes, but even in lighter ones sometimes. And other times I did not really see it. I always assumed it had to do with the Jpg engine and sensor of the K20. Since I was not shooting raw, I blamed myself more than the camera.

asdf · 01-13-2010, 11:22 AM

Originally posted by Laurentiu Cristofor

Tried that and it doesn't work to me - not in preview, not at 100%. Could it just be a problem with some cameras, or could it be that it requires the sensor to be used a lot before this starts showing up, or could it be interference from some other electronic device?

Was your exposure such that the black surface appeared gray (i.e., it was not completely clipped)?

01-12-2010, 07:18 AM	#47
pcarfan Veteran Member Join Date: Sep 2007 Location: Dayton, Ohio Photos: Gallery \| Albums Posts: 2,978 Original Poster	Originally posted by JohnBee PS. on the other hand, I was not able to the original images, do you have a link? Perhaps it's time to get my glasses changes The original images were posted in another thread... FULL res 6400 (So a very large file) Flickr Photo Download: FULL RES (3 of 3) FULL res 3200 (So a very large file) Flickr Photo Download: FULL RES (2 of 3) FULL res 1600 (large file) Flickr Photo Download: FULL RES (1 of 3) P.S: John, that image you posted was absolutely fabulous irrelevant to what iso was used. Last edited by pcarfan; 01-12-2010 at 07:27 AM.

01-12-2010, 07:23 AM	#48
pcarfan Veteran Member Join Date: Sep 2007 Location: Dayton, Ohio Photos: Gallery \| Albums Posts: 2,978 Original Poster	Originally posted by Laurentiu Cristofor What I see in that area looks more like JPEG compression artifacts............If pcarfan's files are scaled down and compressed, what we might be seeing here are just side-effects of the algorithms used for scaling down and compressing the images. I've looked at his 3200 shot in original size and banding isn't half as obvious as it is in his OP. I opened the same image in Rawtherapee ( to rule out LR causing it) and then exported to photoshop and saw the banding when viewed there and thus assumed it is neither the raw program nor the jpeg compression. So, I re-did the test now, but paid more careful attention to the image in rawtherapee before exporting and the banding is much less. Here is the screen capture. I think there is less banding there, but there is still some. The same image posted before (opened in LR and saved as Jpeg) Last edited by Damn Brit; 01-13-2010 at 02:24 AM. Reason: added imgwide tags

01-13-2010, 02:21 AM	#57
Igilligan Guest	Hey a quick question for those seeing the banding Do you have battery grips on your cameras?

01-13-2010, 10:20 AM	#59
Igilligan Guest	Lucky you on the DA 15!!!! I can't remember seeing any Retro firmware threads. Good luck with that search. Are you getting the horz banding in all your ISO 3200> shots? I did not think it was that bad in the test shots you posted here. I guess it is like PF... once you see it you cant help but see it. I shot the Tammy 70-300 for a month before someone started talking about PF in one of my bird shots. After that... it was everywhere. If I did that to you on this K20/k7 banding, I am truly sorry. From my point of view it was never really an issue for me. On my k20 I would see it worse in some scenes and not at all in others. There seemed to be no real consisistancy in what caused it. Sometimes it showed up in darker parts of the scenes, but even in lighter ones sometimes. And other times I did not really see it. I always assumed it had to do with the Jpg engine and sensor of the K20. Since I was not shooting raw, I blamed myself more than the camera. Last edited by Igilligan; 01-13-2010 at 10:29 AM.

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01-12-2010, 02:37 AM	#46
JohnBee Veteran Member Join Date: Sep 2008 Location: Newrfoundland Photos: Albums Posts: 4,667	I woundn't know where to begin with a response tbh.

01-12-2010, 07:39 AM	#49
asdf Veteran Member Join Date: Jan 2009 Location: Canada Posts: 1,252	Originally posted by pcarfan I opened the same image in Rawtherapee ( to rule out LR causing it) and then exported to photoshop and saw the banding when viewed there and thus assumed it is neither the raw program nor the jpeg compression. So, I re-did the test now, but paid more careful attention to the image in rawtherapee before exporting and the banding is much less. Here is the screen capture. I think there is less banding there, but there is still some. BTW, this is a picture-peeping problem not a pixel peeping one. You can see the horizontal pattern when you look at the entire picture. The horizontal discolorations become less distinct when you zoom in. If you can make a printout on a dye-sub printer, tell us if it looks better or worse.

01-12-2010, 07:48 AM	#50
pcarfan Veteran Member Join Date: Sep 2007 Location: Dayton, Ohio Photos: Gallery \| Albums Posts: 2,978 Original Poster	I checked with some other images, opened in RawTherapee , and the banding is there with the more recent images. So, I am fairly certain it's not the Raw converter nor the jpeg compression.

01-12-2010, 07:54 AM	#51
asdf Veteran Member Join Date: Jan 2009 Location: Canada Posts: 1,252	Originally posted by pcarfan I checked with some other images, opened in RawTherapee , and the banding is there with the more recent images. So, I am fairly certain it's not the Raw converter nor the jpeg compression. Yeah, I see the pattern in the camera preview even. For others, who haven't noticed this, all you have to do to replicate this is to crank ISO to the max and shoot a uniformly black surface (or any composition with a uniformly black surface).

01-12-2010, 08:49 AM	#52
Mr.Turnip Junior Member Join Date: Jan 2007 Location: Denmark Posts: 33	Originally posted by Igilligan Dang I really got to read this manual. You mean I can change metering between spot center matrix with the info / thumbwheel? I have been bangin back and forth thru the darn menu. A real pain... YEP THERE IT IS Thank you Claus >>> I really have to read the manual!!! Hahaha what an idiot I am Next time I am giving any advice or giving anyone any grief... Please link to this post! LOOOL - no problem..glad you found out I didn't read the manual either, I just pushed all the buttons I could ...but I'm glad I did discover it...it's a pretty neat feature

01-12-2010, 10:05 AM	#53
SergioFromSF Junior Member Join Date: Dec 2009 Location: San Francisco Photos: Albums Posts: 45	Yes, great image! I too would love to learn to take and pp such an image quality.

01-12-2010, 01:19 PM	#54
pcarfan Veteran Member Join Date: Sep 2007 Location: Dayton, Ohio Photos: Gallery \| Albums Posts: 2,978 Original Poster	Yeah! JohnBee I hope you will come through with those steps. In my monitor, the faces of the two girls towards the left end seem to have a bit more 'burning' than the rest, but otherwise that image was absolutely awesome.

01-12-2010, 01:46 PM	#55
JohnBee Veteran Member Join Date: Sep 2008 Location: Newrfoundland Photos: Albums Posts: 4,667	Originally posted by pcarfan Yeah! JohnBee I hope you will come through with those steps. In my monitor, the faces of the two girls towards the left end seem to have a bit more 'burning' than the rest, but otherwise that image was absolutely awesome. Thanks everyone for your kind comments. I'll look into putting together a walkthrough of the steps I used for that image.

01-13-2010, 02:12 AM	#56
Laurentiu Cristofor Banned Join Date: Nov 2009 Location: WA Photos: Albums Posts: 3,055	Originally posted by JohnBee Having said that... the banding is well and accounted for in all three images at 100% as well as the resized ones. It's obvious to me in the resized 6400 image. But I don't notice it in the other images - not as obvious as that 6400 or dpreview's images, anyway. Originally posted by pcarfan I opened the same image in Rawtherapee ( to rule out LR causing it) and then exported to photoshop and saw the banding when viewed there and thus assumed it is neither the raw program nor the jpeg compression. So, I re-did the test now, but paid more careful attention to the image in rawtherapee before exporting and the banding is much less. Here is the screen capture. I think there is less banding there, but there is still some. <image removed from quote to save space> The same image posted before (opened in LR and saved as Jpeg) <image removed from quote to save space> I can definitely see banding in the original image, although it's not obvious to me when looking at the original size. The new capture looks much better to me - if there's banding in it, it's below what I'd notice. I don't know what to say. I only use the Pentax software for conversion - I never used LR. I did use RawTherapee a few times to see if I can get better raw processing from it and what I noticed was that: a) Pentax software was still better b) when examining images at 100%, RawTherapee ones looked as if they were painted with a brush - I assume their algorithms are much more different than the Pentax ones. Originally posted by asdf Yeah, I see the pattern in the camera preview even. For others, who haven't noticed this, all you have to do to replicate this is to crank ISO to the max and shoot a uniformly black surface (or any composition with a uniformly black surface). Tried that and it doesn't work to me - not in preview, not at 100%. Could it just be a problem with some cameras, or could it be that it requires the sensor to be used a lot before this starts showing up, or could it be interference from some other electronic device?

01-13-2010, 04:01 AM	#58
pcarfan Veteran Member Join Date: Sep 2007 Location: Dayton, Ohio Photos: Gallery \| Albums Posts: 2,978 Original Poster	Originally posted by Igilligan Do you have battery grips on your cameras? No, I don't. I am fairly convinced it is the firmware update that also included the FineSharpness2 settings, and I need to find out how I can get back to the original firmware. Any ideas? P.S: I went ahead and ordered the DA15 yesterday, couldn't resist the small packaging

01-13-2010, 11:22 AM	#60
asdf Veteran Member Join Date: Jan 2009 Location: Canada Posts: 1,252	Originally posted by Laurentiu Cristofor Tried that and it doesn't work to me - not in preview, not at 100%. Could it just be a problem with some cameras, or could it be that it requires the sensor to be used a lot before this starts showing up, or could it be interference from some other electronic device? Was your exposure such that the black surface appeared gray (i.e., it was not completely clipped)?