Help with ISO?

ric_cr · 12-16-2019, 06:06 PM

Hello, I hope you are well, wishing you happy holidays.

For some time I began to notice that in some photos, something similar to a granulate appears, that I am not sure if it is ISO problem, trepidation or I just made a poorly focused work.

I attach some images. Camera: K-3 II Lens: SMC Pentax-F 50mm F1.7 ISO: 320 F: 1.7 Shutter Speed: 1/25 (without tripod)

In case it is a problem with the ISO system, (I don't think so) can it be fixed? I'm not used to taking pictures in buildings and less in low light.

Thanks.

Attached Images

Paul the Sunman · 12-16-2019, 06:16 PM

Apart from the bright rings around the out-of-focus highlights (which is a lens thing), I don't see much wrong with this! It is a little soft at the highest magnification, which is expected for that lens wide open; quite appropriate for the subject anyway. Very nice shot.

**dms** · 12-16-2019, 06:21 PM

Looks great to me. A really optically beautiful lens from this image. Combination of at or near 100% resolution and natural skin not being uniform/smooth when viewed close up.

bertwert · 12-16-2019, 06:21 PM

The 'granulate' is noise, which is apparent at higher ISO settings:
Image noise - Wikipedia

StarTroop · 12-16-2019, 06:40 PM

That's just digital noise, nothing to worry about, and not at all detracting from your photo. Considering you don't seem to be totally familiar with the effects of increasing ISO, I'm assuming you also don't process your photos manually from Raw. The built-in jpeg processors in cameras and the default raw processing profiles in Lightroom etc., aren't always the most effective at reducing noise, or they're too effective to the point of reducing detail. With manual processing you could theoretically do a better job at hiding the luminance noise (chrominance noise seems to be well corrected already), but luminance noise is typically better regarded because it's somewhat similar to film grain, and if you need to zoom in to 100% just to see the noise then it's definitely not severe enough to require further correction, so I would leave it as is.

FYI, you seem to have gone for a lifted shadows look, which means exposure in the darkest areas has been uniformly lifted, which will amplify the noise in those areas. Again, I wouldn't call it an issue in this picture, but if you try to do the same effect at even higher ISOs you will eventually exacerbate the noise enough that it becomes noticeable. I'm not familiar with the K3ii's practical limits, but you're probably completely safe bumping ISO up to at least 1600.

photoptimist · 12-16-2019, 06:44 PM

Strange! It's not normal ISO noise. It looks like you are applying some filter than is too strong. Notice how some of the stray hairs and edges have a halo of granules.

What in-camera image settings do you use or what post processing do you do?

**GUB** · 12-16-2019, 07:03 PM

I agree with Photoptimist - it is not normal noise. It is something to do with processing. Any chance of a raw?

stevebrot · 12-16-2019, 07:27 PM

Originally posted by photoptimist

Strange! It's not normal ISO noise. It looks like you are applying some filter than is too strong. Notice how some of the stray hairs and edges have a halo of granules.

What in-camera image settings do you use or what post processing do you do?

Originally posted by GUB

I agree with Photoptimist - it is not normal noise. It is something to do with processing. Any chance of a raw?

What they said. ^ ^ ^ Bit-depth issue?

A few questions:

What camera?
What kind of capture: DNG/PEF or JPEG?
What tools were used for post processing?

Steve

ric_cr · 12-16-2019, 07:28 PM

Originally posted by photoptimist

Strange! It's not normal ISO noise. It looks like you are applying some filter than is too strong. Notice how some of the stray hairs and edges have a halo of granules.

What in-camera image settings do you use or what post processing do you do?

In camera settings page 1:
Digital filter: OFF
hdr capture: off
Pixel Shift Resolution: Off

Settings page 2:
D-Range Settings: off off (Highlight Correction and Shadow Correction)
High ISO Noise Reduction: Off
Slow Shutter Speed NR: Off

Settings Page 3:

AA filter simulator: off

All other settings in the "C" page are in default

I attach images from the raw

---------- Post added 12-16-19 at 08:35 PM ----------

Originally posted by stevebrot

What they said. ^ ^ ^ Bit-depth issue?

A few questions:

What camera?
What kind of capture: DNG/PEF or JPEG?
What tools were used for post processing?

Steve

I quote photoptimist with some images from the raw, camera: k3-ii, raw: dng and for the processing i only use lightroom.

in the attached images of the raw you can see more the
granulated

stevebrot · 12-16-2019, 08:07 PM

Originally posted by ric_cr

I quote photoptimist with some images from the raw, camera: k3-ii, raw: dng and for the processing i only use lightroom.

What processing was done in Lightroom? Are you using plugins?

Is there any way you can provide a link to the original DNG to allow download from cloud storage, dropbox, or similar? The attached files tell us little except that the image was likely over-processed. The actual DNG with EXIF intact might provide some clues as to how that might have happened in post-processing.

Addendum: The exposure information (f/1.7, 1/25s, ISO 350) indicates rather dim conditions. What exposure mode was used? Auto-ISO?

Steve

ric_cr · 12-16-2019, 09:37 PM

Originally posted by stevebrot

What processing was done in Lightroom? Are you using plugins?

Is there any way you can provide a link to the original DNG to allow download from cloud storage, dropbox, or similar? The attached files tell us little except that the image was likely over-processed. The actual DNG with EXIF intact might provide some clues as to how that might have happened in post-processing.

Addendum: The exposure information (f/1.7, 1/25s, ISO 350) indicates rather dim conditions. What exposure mode was used? Auto-ISO?

Steve

Sure, here the link. I attach two raw dng from the same day with very similar conditions.

Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.

**GUB** · 12-16-2019, 09:52 PM - **1 Like**

Na it is something to do with settings in your developer. This is screenshot Darktable +1.5 EV and nothing else but base image settings.

Sandy Hancock · 12-16-2019, 10:03 PM

The cropped image in the original post looks like it has had some over-zealous noise reduction in post processing.

**GUB** · 12-16-2019, 10:09 PM

I think the issue may be in part trying to sharpen an image that is not quite sharp creating artifacts with other adjustments. I think you have to just enjoy what is a lovely image at a more base setting. Let us know what you find.

stevebrot · 12-16-2019, 10:13 PM

Originally posted by ric_cr

Sure, here the link. I attach two raw dng from the same day with very similar conditions.

Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.

Thanks! I took a quick look at the one for the original post. When I looked at the embedded preview JPEG and a quick development of the DNG in the Pentax DCU software, it is apparent the image is mildly underexposed and pretty soft, probably due to a combination of camera motion and missed focus.

I will take a closer look using Lightroom.

Steve

12-16-2019, 06:06 PM	#1
ric_cr New Member Join Date: Mar 2015 Location: San Jose Posts: 18	Help with ISO? Hello, I hope you are well, wishing you happy holidays. For some time I began to notice that in some photos, something similar to a granulate appears, that I am not sure if it is ISO problem, trepidation or I just made a poorly focused work. I attach some images. Camera: K-3 II Lens: SMC Pentax-F 50mm F1.7 ISO: 320 F: 1.7 Shutter Speed: 1/25 (without tripod) In case it is a problem with the ISO system, (I don't think so) can it be fixed? I'm not used to taking pictures in buildings and less in low light. Thanks. Attached Images

12-16-2019, 07:28 PM	#9
ric_cr New Member Join Date: Mar 2015 Location: San Jose Posts: 18 Original Poster	Originally posted by photoptimist Strange! It's not normal ISO noise. It looks like you are applying some filter than is too strong. Notice how some of the stray hairs and edges have a halo of granules. What in-camera image settings do you use or what post processing do you do? In camera settings page 1: Digital filter: OFF hdr capture: off Pixel Shift Resolution: Off Settings page 2: D-Range Settings: off off (Highlight Correction and Shadow Correction) High ISO Noise Reduction: Off Slow Shutter Speed NR: Off Settings Page 3: AA filter simulator: off All other settings in the "C" page are in default I attach images from the raw ---------- Post added 12-16-19 at 08:35 PM ---------- Originally posted by stevebrot What they said. ^ ^ ^ Bit-depth issue? A few questions: What camera? What kind of capture: DNG/PEF or JPEG? What tools were used for post processing? Steve I quote photoptimist with some images from the raw, camera: k3-ii, raw: dng and for the processing i only use lightroom. in the attached images of the raw you can see more the granulated Attached Images

12-16-2019, 08:07 PM	#10
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by ric_cr I quote photoptimist with some images from the raw, camera: k3-ii, raw: dng and for the processing i only use lightroom. What processing was done in Lightroom? Are you using plugins? Is there any way you can provide a link to the original DNG to allow download from cloud storage, dropbox, or similar? The attached files tell us little except that the image was likely over-processed. The actual DNG with EXIF intact might provide some clues as to how that might have happened in post-processing. Addendum: The exposure information (f/1.7, 1/25s, ISO 350) indicates rather dim conditions. What exposure mode was used? Auto-ISO? Steve Last edited by stevebrot; 12-16-2019 at 08:26 PM.

12-16-2019, 09:52 PM - 1 Like	#12
GUB Loyal Site Supporter Join Date: Aug 2012 Location: Wanganui Photos: Gallery \| Albums Posts: 5,760	Na it is something to do with settings in your developer. This is screenshot Darktable +1.5 EV and nothing else but base image settings. Attached Images

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12-16-2019, 06:16 PM	#2
Paul the Sunman Pentaxian Join Date: Aug 2011 Location: Melbourne Photos: Gallery Posts: 4,846	Apart from the bright rings around the out-of-focus highlights (which is a lens thing), I don't see much wrong with this! It is a little soft at the highest magnification, which is expected for that lens wide open; quite appropriate for the subject anyway. Very nice shot.

12-16-2019, 06:21 PM	#3
dms Site Supporter Join Date: Aug 2011 Location: New York, NY Photos: Gallery Posts: 2,192	Looks great to me. A really optically beautiful lens from this image. Combination of at or near 100% resolution and natural skin not being uniform/smooth when viewed close up.

12-16-2019, 06:21 PM	#4
bertwert Veteran Member Join Date: Jun 2015 Location: Golden, BC Posts: 15,172	The 'granulate' is noise, which is apparent at higher ISO settings: Image noise - Wikipedia

12-16-2019, 06:40 PM	#5
StarTroop Senior Member Join Date: Feb 2018 Posts: 175	That's just digital noise, nothing to worry about, and not at all detracting from your photo. Considering you don't seem to be totally familiar with the effects of increasing ISO, I'm assuming you also don't process your photos manually from Raw. The built-in jpeg processors in cameras and the default raw processing profiles in Lightroom etc., aren't always the most effective at reducing noise, or they're too effective to the point of reducing detail. With manual processing you could theoretically do a better job at hiding the luminance noise (chrominance noise seems to be well corrected already), but luminance noise is typically better regarded because it's somewhat similar to film grain, and if you need to zoom in to 100% just to see the noise then it's definitely not severe enough to require further correction, so I would leave it as is. FYI, you seem to have gone for a lifted shadows look, which means exposure in the darkest areas has been uniformly lifted, which will amplify the noise in those areas. Again, I wouldn't call it an issue in this picture, but if you try to do the same effect at even higher ISOs you will eventually exacerbate the noise enough that it becomes noticeable. I'm not familiar with the K3ii's practical limits, but you're probably completely safe bumping ISO up to at least 1600.

12-16-2019, 06:44 PM	#6
photoptimist Pentaxian Join Date: Jul 2016 Photos: Albums Posts: 5,127	Strange! It's not normal ISO noise. It looks like you are applying some filter than is too strong. Notice how some of the stray hairs and edges have a halo of granules. What in-camera image settings do you use or what post processing do you do?

12-16-2019, 07:03 PM	#7
GUB Loyal Site Supporter Join Date: Aug 2012 Location: Wanganui Photos: Gallery \| Albums Posts: 5,760	I agree with Photoptimist - it is not normal noise. It is something to do with processing. Any chance of a raw?

12-16-2019, 07:27 PM	#8
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by photoptimist Strange! It's not normal ISO noise. It looks like you are applying some filter than is too strong. Notice how some of the stray hairs and edges have a halo of granules. What in-camera image settings do you use or what post processing do you do? Originally posted by GUB I agree with Photoptimist - it is not normal noise. It is something to do with processing. Any chance of a raw? What they said. ^ ^ ^ Bit-depth issue? A few questions: What camera? What kind of capture: DNG/PEF or JPEG? What tools were used for post processing? Steve

12-16-2019, 09:37 PM	#11
ric_cr New Member Join Date: Mar 2015 Location: San Jose Posts: 18 Original Poster	Originally posted by stevebrot What processing was done in Lightroom? Are you using plugins? Is there any way you can provide a link to the original DNG to allow download from cloud storage, dropbox, or similar? The attached files tell us little except that the image was likely over-processed. The actual DNG with EXIF intact might provide some clues as to how that might have happened in post-processing. Addendum: The exposure information (f/1.7, 1/25s, ISO 350) indicates rather dim conditions. What exposure mode was used? Auto-ISO? Steve Sure, here the link. I attach two raw dng from the same day with very similar conditions. Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.

12-16-2019, 10:03 PM	#13
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,275	The cropped image in the original post looks like it has had some over-zealous noise reduction in post processing.

12-16-2019, 10:13 PM	#15
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by ric_cr Sure, here the link. I attach two raw dng from the same day with very similar conditions. Microsoft OneDrive - Access files anywhere. Create docs with free Office Online. Thanks! I took a quick look at the one for the original post. When I looked at the embedded preview JPEG and a quick development of the DNG in the Pentax DCU software, it is apparent the image is mildly underexposed and pretty soft, probably due to a combination of camera motion and missed focus. I will take a closer look using Lightroom. Steve