Settings of module not maintained when copying history stack

Software darktable
1

Hi all, I just noticed that when copying the history stack of an image to another image, the setting/value of a module is not kept. For example I apply the equalizer module with preset ‘sharpen’ and an amount of 0.750 to an image. I go back to the lighttable, copy the history stack from the image to another (making sure all applicable modules are copied) and I apply them to another image. When I go to darkroom for this second image, the equalizer module is enabled (it has applied this when copying the history stack) but the the set value 0.75 is lost and is back to 1.

I have noticed this behavior with some other modules as well, but can’t remember which ones exactly. I’m running 2.6.3 on windows 10 64bit

2

Hi @Dinobe,

I presume you mean the “mix” setting.
Is it still 0.75 in your original/your first image,
or has that, as well, been changed into 1?

Have fun!
Claes in Lund, Sweden

3

Yes, I do mean the mix setting
I’ll check if the original image is back to 1 but I don’t think so

I have noticed this in version 2.6.2 and 2.6.3 on windows. I’ll have a look on my Linux machine as well

4

Hi @Claes

I checked in on my windows machine, and the mix value of the original image is back to 1.
BUT: it seems it resets itself to 1 when going from darkroom to lighttable.

In detail: I select and image in lighttable, go to darkroom, apply the Equalizer module, preset sharpen with mix 0.7, go back to lighttable and go back to darkroom with the same image selected. The value of mix in Equalizer module is back to 1.

The copy history stack from my opening post will probably work correctly, it’s just that the value is lost/reset when going from darkroom to lighttable

I checked: same happens my linux machine, Xubuntu 19.10, DT 2.6.2

5

Well, @Dinobe,
It looks like you have found a little bug. Please register it here:

Also: you can find the same behaviour in dt 2.7.0+2092 (Linux git version).

Easiest way to duplicate the error is to expand the contrast equalizer module, change mix to any value, say 1.5, then perform a single click inside the equalizer window. The present curve will not change, but the mix factor will reset to 1.

Have fun!
Claes in Lund, Sweden

6

I have noticed this behavior with the equalizer too, but look at the line you adjust in the module when you copy. To me it looks like the mix just brings down the line in the “equalizer” part, if that makes any sense.

7

Yes, you are right, when changing the mix value, by moving the slider and then clicking somewhere on the curve, the mix value changes back to 1…

8

Always better to check for previous issues:
https://github.com/darktable-org/darktable/issues/3095

9

Hi, apparently this is not a bug, but it works like intended. The mix slider is used to push/pull all nodes in the graph simultaneously. it’s a tool of the module, not a value which has an effect on the image.

Confusing IMHO, but once you know that does what it does, I’m fine with it.

10

This will be fixed as discussed in one of the PR about this issue.