Using Tone Equalizer (Scene Referred) (Solved)

Software darktable
1

Darktable 4.2, settings for scene-referred processing.
Pixel Pipe has following modules (bottom to top):

Denoise
Lens Correction
Exposure
Tone Equalizer
Color Calibration
Color Balance RGB
Sigmoid
Local Contrast

After use of Exposure module I pull up Tone Equalizer.
However in Tone Eq my cursor turns into a solid black circle with a "?EV when I move my cursor over parts of the image. In Display-Referred, for same image I get EV values as I move cursor over image.
Q1: What could I be doing wrong?
Q2: Shouldn’t Tone Eq follow Color Calib and/or Color Bal RGB? Why is it so early in the pixel pipe i.e., even before I use Color Calib to convert image to B&W?

In Lens Correction, darktable 4.0 and prior auto-recognized pics taken by my 55mm Micro-Nikkor under “Nikon AF Micro-Nikkor 55 mm f/2.8”. darktable 4.2 seems to not (automatically) recognize that lens; every shot I took with the 55mm Micro-Nikkor requires I choose the equivalent lens listed as “Nikkor AI-S 55mm f/2.8 Micro” in the list under “Corrections” (for Nikon lens).
Q3: Is this a darktable bug? what do I need to do for darktable to continue to recognize what it used to earlier?

1 Like
2

You don’t always need the tone equalizer, only if you want to selectively darken or lighten parts of the image.
Detailed video from its original author: darktable 3.0 : dodging and burning with the tone equalizer - YouTube
You’ll also find others on YouTube.
It is early in the pipeline, because it’s an exposure adjustment, not colour.

3

Yes, I understand I don’t always need the Tone Eq.
I’m converting several images to B&W and would like to dodge/burn (most, if not all) of them during processing. My Q is less about the need to use Tone Eq and more about “why” I’m unable to use it in the pixel pipe listed earlier (when I could use it in display-referred).

4

‘?’ sign: the module is disabled.
image

EV is displayed, when the module is enabled:
image

5

Make sure that your mask is well defined – this is described in the manual.

6

Are you adjusting the mask using the eye droppers in mask exposure compensation and mask contrast compensation on the masking tab?

No, its basically the same thing as Exposure but with fancy masking. It only works on the lightness of the images not the color. But you should move it after the modules you mention and see what happens.

7

Perfect, thank you, Istvan, operator error on my part that you have made me aware of!
And, yes, Miguel, the times I got Tone Eq “enabled” and working I was able to get the mask well defined per the manual.
Very silly of me to not enable the module and wonder why I was not able to use it! I’ve used up my quota of silliness for the day…