apply pixel workflow and color calibration v5.01

Software darktable
1

Hello out there

I am having difficulty with the auto apply pixel workflow defaults set to none (pwdsn) in preferences\processing with the color calibration
module. I am getting a white balance module error when adjustig the grey tab for black and white conversion. After hours of testing I came up witha something to reproduce what
is causing the error message. There are two different types of histories for the none setting in pwdsn.

History setting 1 (HS1) comprises of the values: orientation,display encoding,output color profile,input color profile, original.
HS1 occurs when the application is starting from scratch or one of the other settings such as the default
scene reffered(filmic) has not been touched before. In this state when using color calibration no error is encounted.

History setting 2 (HS2) comprises of the values: orientation, highlight reconstruction, white balance, display encoding, output color profile, input color profile, demosiac, raw/black white point, original
HS2 occurs when the scene refferred (filmic, sigmoid) or (display refferred legacy) is changed to none then changed back to scene refferred (filmic, sigmoid) or (display-reffered legacy)
and then changed back to none. After that HS2 becomes the default for pwdsn none in all filmroles whether HS1 or HS2 were originally applied.
Because of the defect I can’t switch back to the values for HS1 no matter what I try.

Workarounds:

The first work around is to turn off the white balance in HS2 before I move on to the color correction module. The application will automatically create a new white balance entry after orientation
in history and the problem does not show up again when going to color correction.

The second workaround is to toggle between scene refferred (filmic, sigmoid) or (display refferred legacy) and then back to none Hit history refresh between toggles. Although the values for HS2 still
remain the same when going to color calibration the error does not appear again.

The third workaround is to go to the color calibration hamburger menu and choose a preset. It doesn’t seem to matter which one. After the preset is applied the error is
cleared from the color calibration module and I can go on working.

The forth workaround is to bring back a full Clonezilla restore of an image of darktable and all the target files where pwdsn filmic was never changed from default. That easily changes when I use the workflow below

Background:

This whole issue started about two days ago. I was processing some dusk-dawn photos and the pwdsn filmic setting was giving me a strong blue cast.
To fix it I reduced the blue with 5 different rgb primary modules. It did get rid of most of the blue but not all. Thinking there must be a better way I did some Googling.
I read an article saying to toggle the pwdsn to none value
and apply the white balance module. The first time I got HSN1 values and moved on to color correction module with no difficulties. As a matter of fact I was so impressed with the none setting (HS1)
that I left it for both color and b&W. Then I fouund that none was not good for some images. Then started toggling back and forth between pwdsn none and pwdsn filmic.
At that point I started to get the HS2 values for none and regardless of when I use none HS1 values have never shown up again without #4 work around
or a full clean install that never had darktable on it.

Thank you for your time. I spent an enormous amount of time trying to figure out what was causing the color calibration error. This is the best I could come up with. I’m really disappointed that before I ran into
this the application seemed stable. I downloaded the source code but it will take me a while to understand the architecture. If anyone has insight on how I can stabalize this issue I would appreciate i.

Victor

2

I got a bit lost in your post but if you set wb to anything but as shot ie the left option or as-shot to reference ie the right most option and then add CC instance it will give you the double wb error… if you use the channel mixer preset or set CAT to bypass in the module the error should go away…its a double WB notification… if you know what you are doing and don’t care then you could ignore it…as for your blue cast share an image in the playraw section and people can help…usually going to v5 with color preservation set to no, or the saturation slider in v7…I have even tried blending filmic v7 in lightness to avoid the gamut mapping that can cause a color cast…but the best way would be to share the image and get help and suggestions… I will try to read your post again and follow exactly what sequence of actions you are taking to generate your issues…

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I am unable to follow your description, sorry. There is no such thing as pwdsn filmic setting or pixel workflow defaults set to none filmic setting, for example.

Try to write more concise posts and use terminology used by the application and by the manual (it’s always a bit outdated, but it exists: darktable user manual - darktable).
Read at least:

You can choose between different workflow options (preferences/processing/auto-apply pixel workflow defaults – darktable user manual - processing, under auto-apply pixel workflow defaults):

  • none: does not apply any tone mapper; uses white balance only (set to as shot by default); module order is the ‘modern’ one. Use this if you know what you are doing and have your own workflow.
  • scene-referred filmic and sigmoid: these use the respective tone mapper (which comes quite late in the pipe), white balance (set to as shot to reference) and color calibration to manage white balance (you have to adjust color calibration in this case, and leave white balance alone). Module order is the ‘modern’ one. Use one of those in most cases.
  • display-referred (legacy): if you want to process the traditional way, with a base curve as the tone mapper (which comes quite early in the pipe – legacy module order). Manage white balance using white balance.

The defaults are not something you change image to image.

Uploading an image and a problematic sidecar may help.

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4

While your post is rather hard to follow, I gather you see some issues and try to solve them by changing the settings in the “preferences” dialog.

Keep in mind that changes there do not have any effect on existing edits.

That white balance error is due to activating a first copy of color calibration. That first copy leaves the CAT tab active. Simplest solution: in the CAT tab set “adaptation” to “none (bypass)”.

If your preferred workflow is indeed “none” and you want to use color calibration for monochrome conversion, you may want to make a preset with the setting described above.

@priort: if color calibration is used for white balancing, the white balance module should be on “as shot to reference” or “camera reference”. The other options (including “as shot”!) will get you the big red warning…

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Starting from one of the provided B&W conversion presets is probably a good idea.

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You’re right, I didn’t think of those.

I noticed they set the CAT adaptation to “XYZ” as well.

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Since it uses as shot I thought I checked before posting and no error but maybe I missed it…

EDIT

Ya thanks…I was sure I had checked it out of curiousity to see what it would do with that combination but I wonder too if I was checking on a previously edited image by disabling things and I had not reset the history stack…in any even you are as always correct…

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Under settings change back to the scene-refered default you want (either filmic or sigmoid)

In the light table: Highlight the file–>history tab (right hand panel)–>discard history.

Enter darkroom. Your History stack (left hand panel) will be the default for the scene-ref’d default you chose.

Once you process a picture with no history stack in the darkroom, whatever choice you have set in settings will then applied to the photo.

For me, changing settings did not change anything on photos which had been previously processed in any filmroll. If those are changing, then there may be a real problem, but I couldnt reproduce it. :person_shrugging:

As for the “error” that shows up in the color calibration model, it is more of an alert than an error in the normal sense. Since you are converting to B&W it really doesnt matter.

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When I convert to B/W with Color Calibration, I just use a new instance.

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If you already use Color Calibration for whitebalancing, the second and following instances “are smart enough” to set the CAT to “bypass”. OP wasn’t using Color Calibration for white balance (only WB module with “as shot”)…

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As do I (in most cases), but mainly because it allows for masks/adjustments based on hue,saturation,etc. I could do the same by other means. I am by no means an expert though.

Is there a reason/benefit other than that?

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For me, its just conceptually a separate step. I tend to use a lot of module instances though.

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You can switch the extra copy on and off to judge the effect without also switching the white balance part. Perhaps less important for conversion to grayscale, but it helps me from going overboard with other corrections.

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The other tabs also work in the adaptation color space, which means that the channel mixer, for example, gives different results.

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I have not used the channel mixer over, say, Color EQ or RGB primaries to help edit B&W. I am interested now. Can you outline a brief exercise that I can start messing about with to see the difference?

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Boris has a pretty good series of 3 video’s starting with this one… https://www.youtube.com/watch?v=Yg0pspIT0nE&t=1850s

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I think we have strayed so far from the problem (or even context) of the orignial post, that perhaps this conversation should migrate to a new thread. Especially considering there has been no further interaction from the original author.

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I had three problems. The first was I was getting a severe blue cast when using the apply pixel workflow This was caused by importing a lightroom xmp file along with the original raw file (.nef). I trashed all the .nef /.xmp files and reformatted my test machine to a clean darktable and re-imported just the .nef files and the problem disappeared.

The second was I received a white balance error when using the any tab area of color calibration while apply pixel workflow was set to none. The fix for this is to go under show only active modules and change white balance as set white balance as shot to set white balance to camera reference point in most cases this should be D65. After that the color calibration error for white balance disappeared and a whole lot of others.

The third problem I had was while trying to fix the first two and mucking around with any solution I could think of. Both the history module and the database corrupted causing strange behaviors. On a very high level the application will allow you to continue which if you do to many changes after the application errors will fail to the point of being non-usable. The only fix I found is after an error message appears immediately reset the offending module and then reset history. It’s not pretty but it saves you from losing work and corrupting the program. Some errors had easy fixes while I had to dig into a color calibration tutorial by Bruce Williams from 4 years ago where he mentions the apply pixel workflow set to D65 when using color caibration. Why, he never explains.

Please note when evaluating darktable I had a test machine that could be restored with a clean image from a backup program. In the beginning until I started to figure what was going on I had to restore at least nine times back to a genesis state of the test machine because the application corrupted so badly. Also I learned the hard way if I worked on an image that came out really well backup the xmp file so if you have to restore the application from scratch you can bring back what you worked on. When using this application I would highly recommend to backup,backup,backup.

Thanks Victor

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The white balance error is now explained in the FAQ: faq | darktable

That’s completely unnecessary. If indeed the settings or database have been corrupted, you only need to delete the folder with the darktable user data.

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