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04-22-2018, 04:22 AM   #151
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I'm using the DNGs from the archive; I opened the ISO 100 and ISO 800 ones in Silkypix, done some adjustments (+1 EV, convert to monochrome because the colors are otherwise slightly different, default sharpening), disable all types of NR and then there's the cycling between the two images. I cannot see any loss of detail.
I could see some subtle difference on the jpegs posted on the forum.

I wanted to see if I could generate a crop similar to the underexposed ISO 100 one, but without detail loss. OTOH given my findings described above, it's less relevant.

04-22-2018, 06:38 AM - 2 Likes   #152
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QuoteOriginally posted by MJKoski Quote
Just load those two to irfanview or some such editor and cycle them.
For this kind of RAW pixel-peepery, people should begin their work by using Iliah Berg's FastRawViewer:

About | FastRawViewer

Amongst it's other features, it has a lot of tools to let people critically appraise RAW's. In this area, it is far more capable than IrfanView
04-22-2018, 08:03 AM   #153
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QuoteOriginally posted by Kunzite Quote
I'm using the DNGs from the archive
In other words, not @MJKoski 's example images. He has not posted the DNG's yet.


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04-22-2018, 08:16 AM   #154
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QuoteOriginally posted by rawr Quote
For this kind of RAW pixel-peepery, people should begin their work by using Iliah Berg's FastRawViewer:
I agree with the comments that part of what we may be seeing is traceable to ACR processing with the embedded profile, though I am not sure why this particular tool should be taken as a reference. Does it have a mode where no curves have been applied?


Steve

04-22-2018, 08:24 AM   #155
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QuoteOriginally posted by MJKoski Quote
@Kunzite: Why would you compare cropped jpg images? I mentioned that you shall have the DNG files. I am 250km away from my offline file storage at the moment.

Just load those two to irfanview or some such editor and cycle them. It does not require 100% perfect eyesight to see differences. Just a device which shows actual pixels. Like standard desktop monitor. Not retina or cellphone screen.
How are you having Adobe handle the Camera Profile? Are you using the embedded profile or the Adobe Standard profile. This makes a big difference. The Adobe profile strips a lot of color data from the embedded profile especially the red channel.

I am still not getting what the problem is you are seeing. It is no surprise that an ISO 800 image will have less detail than an ISO 100 image.
04-22-2018, 08:49 AM   #156
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QuoteOriginally posted by stevebrot Quote
I agree with the comments that part of what we may be seeing is traceable to ACR processing with the embedded profile, though I am not sure why this particular tool should be taken as a reference. Does it have a mode where no curves have been applied?


Steve
When I read about this viewer that was my understanding.

In CaptureOne Pro we can choose the linear curve and don‘t do any adjustments. That should also give a fully flat vision of an image.

Maybe also the K-1 in camera custom profile natural or flat offers something similar?!
04-22-2018, 09:51 AM   #157
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QuoteOriginally posted by stevebrot Quote
In other words, not @MJKoski 's example images. He has not posted the DNG's yet.


Steve
And that could explain why I couldn't find a similar patch of fur

04-22-2018, 10:31 AM   #158
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QuoteOriginally posted by acoufap Quote
Maybe also the K-1 in camera custom profile natural or flat offers something similar?!
_
Those are JPEG only.


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04-22-2018, 10:32 AM   #159
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QuoteOriginally posted by Rico Quote
How are you having Adobe handle the Camera Profile? Are you using the embedded profile or the Adobe Standard profile.
There is no "Adobe Standard" yet for the K-1II. The example images have been from the embedded profile. It might be interesting to compare the embedded profile for the K-1 with that from the K-1II. There is a tool (dcpTool) that does extraction as well as decompile/compile of embedded and file-based (.dcp files) profiles for editing. Of interest to this discussion are provisions to make profiles invariate such that dynamic curve adjustments are not made in response to changes of the "exposure" or "brightness" sliders.

http://dcptool.sourceforge.net/Introduction.html


Steve

Last edited by stevebrot; 04-22-2018 at 10:45 AM.
04-22-2018, 10:43 AM   #160
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QuoteOriginally posted by stevebrot Quote
Those are JPEG only.


Steve
I know. I’d like to know if one of these doesn’t have any curve or other tweaks applied. If not, it would be the way to go when using the histogram. Of course it´s not a raw histogram like in the mentioned viewer.
04-22-2018, 10:51 AM   #161
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QuoteOriginally posted by acoufap Quote
When I read about this viewer that was my understanding.
If it is there, I could not find it in the documentation.


Steve
04-22-2018, 10:52 AM   #162
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QuoteOriginally posted by stevebrot Quote
Of interest to this discussion are provisions to make profiles invariate such that dynamic curve adjustments are not made in response to changes of the "exposure" or "brightness" sliders.
If one was to change the base line exposure in the exif data and offset it to accommodate the push needed we should be able to circumvent much of that, one could also build a custom profile for the mrk 2

---------- Post added 04-22-2018 at 10:57 AM ----------

QuoteOriginally posted by rawr Quote
For this kind of RAW pixel-peepery, people should begin their work by using Iliah Berg's FastRawViewer:
When using FRV you would be surprised as to how much NR is being done to the raw files by raw converters behind the curtains.
04-22-2018, 11:53 AM   #163
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QuoteOriginally posted by stevebrot Quote
In other words, not @MJKoski 's example images. He has not posted the DNG's yet.


Steve
He has posted DNGs...

(link above in this thread), but here it's again:

2018-04-16.7z - Google Drive
04-22-2018, 12:11 PM - 1 Like   #164
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I see no smoothing at ISO 1600 either, by the way. There is obviously some noise (that's effectively an ISO 3200, as it's underexposed by a stop) but no detail loss attributable to some compulsory RAW NR.

I won't go to ISO 3200 (effectively ISO 6400) as I'd be looking at noise starting to obscure detail. Myth busted
04-22-2018, 12:21 PM   #165
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QuoteOriginally posted by aikaarska Quote
He has posted DNGs...

(link above in this thread), but here it's again:

2018-04-16.7z - Google Drive
Ha! Ha! I thought those were your images since the were posted by you in response to doubts about your claims, particularly since you seem to have all the answers about their intent. BTW...all of the group for which we have the DNG shared the same LV and all are about 2/3 stop underexposed.

The most recent questions are in regards to the second round of fur posted by MJKoski, those which demonstrated data loss at ISO 800 and for which we have no DNG*. The DNG for those were promised for whenever they get back to their computer.

QuoteOriginally posted by MJKoski Quote
I mentioned that you shall have the DNG files. I am 250km away from my offline file storage at the moment.

Steve

* I did not spend much time on the Finnish site since I don't trust the translation. I just now saw the second two fur images at the bottom of the forum post page and the signature links indicating that the Maffer who posted the fur photos is our own MJKoski.
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