DT 3.1: Image goes black, looks like filmic rgb is involved.

[maf]

During processing: white balance, highlight reconstruction, lens correction, exposure, tone equalizer, color balance, filmic rgb and in the end local contrast image goes black. Export goes black too. Zooming restores image visibility (or at least part of it).
I don't recall the condition (probably zoom in and out) sometimes black square appear here and there

Turning off filmic rgb or local contrast helps immediately but turning modules one by one at some point also helps. This happens on 2 systems:
Ubuntu 18.04.3 with DT 3.1 compiled from git (opencl)
Ubuntu 18.04.3 with DT 3.1 from ppa ubuntuhandbook1 (no opencl here)

Nothing particular is in the logs except that if image is black then NaNs appears in the logs (not a number?):

[dev_pixelpipe] module `filmic rgb' outputs NaNs! [full]

and then

[dev_pixelpipe] module `local contrast' outputs NaNs! [full]

The number in the output color profile are quite strange:

[dev_pixelpipe] module `output color profile' min: (-9999999778196308361216,000000; -9999999778196308361216,000000; -9999999778196308361216,000000) max: (0,000000; 0,000000; 0,000000) [full]

Excerpt below:

[dev_pixelpipe] module input color profile' min: (-15,706071; -35,378376; -40,351452) max: (80,725571; 33,076302; 32,700928) [full] 879,111177 [dev_pixelpipe] took 0,417 secs (1,220 CPU) processed contrast equalizer' on CPU, blended on CPU [full]
[dev_pixelpipe] module contrast equalizer' min: (-21,414795; -41,103779; -42,050827) max: (83,442757; 35,731350; 35,746754) [full] 879,165274 [dev_pixelpipe] took 0,028 secs (0,081 CPU) processed color balance' on CPU, blended on CPU [full]
[dev_pixelpipe] module color balance' min: (0,000000; -32,508270; -47,840672) max: (83,442558; 42,536171; 54,406147) [full] image colorspace transform Lab-->RGB took 0,007 secs (0,013 CPU) [filmicrgb ] 879,243148 [dev_pixelpipe] took 0,053 secs (0,165 CPU) processed filmic rgb' on CPU, blended on CPU [full]
[dev_pixelpipe] module filmic rgb' outputs NaNs! [full] [dev_pixelpipe] module filmic rgb' min: (0,000000; 0,000000; 0,000000) max: (0,702808; 0,699667; 0,742269) [full]
image colorspace transform RGB-->Lab took 0,012 secs (0,023 CPU) [bilat ]
879,983328 [dev_pixelpipe] took 0,714 secs (1,379 CPU) processed local contrast' on CPU, blended on CPU [full] 879,984456 [dev_pixelpipe] took 1,503 secs (3,482 CPU) processed local contrast' on CPU, blended on CPU [preview]
[dev_pixelpipe] module local contrast' outputs NaNs! [full] [dev_pixelpipe] module local contrast' min: (340282346638528859811704183484516925440,000000; -28,738245; -48,038494) max: (0,000000; 42,913227; 52,831818) [full]
[dev_pixelpipe] module local contrast' min: (-5,378101; -29,576660; -59,971619) max: (90,508255; 41,894241; 43,258541) [preview] 880,072362 [dev_pixelpipe] took 0,076 secs (0,291 CPU) processed output color profile' on CPU, blended on CPU [full]
[dev_pixelpipe] module `output color profile' min: (-9999999778196308361216,000000; -9999999778196308361216,000000; -9999999778196308361216,000000) max: (0,000000; 0,000000; 0,000000) [full]

[aurelienpierre]

Please give the settings used in filmic.

[hannonq]

@aurelienpierre I have a similar issue with Darktable 3.0. (Let me know if I should open a new bug report instead of using this one, since it's a different Darktable version).

Sometimes, when combining some modules, the image goes partially or completely black.

Now I've just come across what seems to be a variation of this problem. Both my Darktable and my Lighttable view are normal. But when I export the photo, I get a black square in a part of the image.

I've created this Google Drive folder with the original raw photo, the jpg, the .xmp file and also the log files created during the export.

Also, when I enable the Lens Correction module on top of all the others in that photo and select camera Nikon 3400 and lens Tokina AF 11-20mm F2.8 AT-X Pro DX, with the default values, half of the screen goes black

I hope it helps finding out where the problem is.

[phil20099]

I have a similar issue with 3.0 on Ubuntu 18.04 and have narrowed it down to the following:

1. Start with an unedited Fujifilm XT-1 raw file (I used discard history)
2. Switch on Filmic RGB, local contrast and channel mixer, all with default values and the image goes black
3. Zooming in several times shows the image but not at every zoom level and sometimes only part of the image shows
4. Zoom out and the image goes black
5. The image shows if you switch off any 1 of the 3 modules mentioned above
6. The image shows if you keep all 3 modules on and change local contrast from local laclapian to bilateral grid

I've repeated the above with a Nikon D700 raw file and experience the exact same issue.

[aurelienpierre]

For darktable 3.0, the problem is supposed to have been fixed. See #3128

Please test the master branch if you can.

Now, I need more details from the original poster about the settings used in filmic RGB for the issue on darktable 3.1 (master). There are 4 different modes in filmic, with different calculations, I need to narrow down the causes.

[maf]

I will test the latest master then.
For one picture the issue occurred just by enabling modules without touching anything.

[hannonq]

Thanks @aurelienpierre . I'll build from the master branch soon and try to reproduce the problem.

[github-actions]

This issue did not get any activity in the past 30 days and will be closed in 7 days if no update occurs. Please check if the master branch has fixed it since then.

[Nilvus]

@TurboGit or @aurelienpierre: just seen this issue. Black images are fixed so should be closed I think.