Color Equalizer Places Nodes Every 45 Degrees?

Software
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I want to check my understanding of the Color Equalizer and hopefully get some understanding about why a certain choice was made.

Why does the Color equalizer module place nodes every 45 degrees instead of every 30 degrees? If the nodes were every 30 degrees, then the nodes’ angle would line up with the named colors of the RGB color wheel:

Standard RGB Color Wheel colors with their angle

Red: 0/360, Primary
Orange: 30, Tertiary
Yellow: 60, Secondary
Chartreuse: 90, Tertriary
Green: 120, Primary
Aquamarine: 150, Tertiary
Cyan: 180, Secondary
Azure: 210, Tertiary
Blue: 240, Primary
Violet: 270, Tertiary
Magenta: 300, Secondary
Rose: 330, Tertiary

As it is, the current node labels seem to be mostly inaccurate:

Current Color Equalizer Nodes

Red: 0, correct
Orange: 45, actually orange-yellow
Yellow: 90, actually chartreuse
Green: 135, actually Green-Aquamarine
Cyan: 180, correct
Blue: 225, actually Azure-Blue
Lavender: 270, should be named violet?
Magenta: 315, Actually Magenta-Rose

Why does this matter?

While I know that color names are simply cultural/lingual constructs, when I edit the colors in photos, I usually think in terms of the standard color wheel divisions of color, and I have often found that I move the “Green” slider and it doesn’t move I think it should, same with yellow, blue, and orange (I don’t often mess with “lavender” and “magenta” much).

Also, almost universally, color wheels are split into twelve sections, almost never 8. I think splitting into the primary, secondary, tertiary colors would be helpful for more accurate naming and ease-of-use.

What am I asking for?

I am not saying we should change the color equalizer module, except perhaps updating the node names to be more accurate, based on a standard RGB color wheel. I would love to know if there is a reason it was designed with 8 nodes spaced every 45 degrees.

I know that Lightroom has 8 hues in its Color Mixer panel, but those seem to be lined up with the named colors on an RGB color wheel instead of evenly spaced (I know this because I am working on converting some Lightroom presets to darktable presets :sweat: ).

Bonus idea

It would be cool if we could pick from two layouts of nodes: even spacing, standard. Even spacing would be what we currently have, and standard would be named colors (0: Red, 30: Orange, 60: Yellow, 120: Green, 180: Cyan, 240: Blue, 300: Magenta, 330: Rose). I am not saying that I want someone to take that on as work, but just throwing out an interesting idea for discussion.

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Not really attempting to answer your question as only the developer of that module can and I believe they have left the DT project and focused their attention on their own product called Ansell.

However, I use both color equalizer and color zones. Shock and horror that I would use a displayed referred module like color zones when color equalizer exists as a scene referred replacement. But I like that color zones is not restricted to specific placement of nodes and I can place within reason as many or as few as I want to affect the specific zones of color.

But then some times I like the sliders in color equalizer and I guess the node placement can be changed but then all nodes shift equally. I will use both modules in the same edit and have presets in both for specific tasks.

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There are eight nodes because that’s usually how many rotary encoders a MIDI controller has. At least the entry-level ones.

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Woah, that seems oddly specific :slight_smile:

Is there a reason they are spaced every 45 degrees?

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Due to how the shortcuts system works, it would otherwise not be possible to adjust them with said MIDI controller.

360 / 8 = 45

I don’t remember if there was any discussion about allowing the nodes to be moved or not.

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Do you have any opinion on those seemingly arbitrary hue angles being labeled with known colors like I talk about in my OP?
I am interested in understanding if other people find this labelling a weird choice like I do.

For general color modifications, I don’t have an issue with an arbitrary number of nodes, but the inaccurate names seem like an oversight in my opinion.

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I don’t use the sliders, so never thought about it. If you search for the discussions when the prototype was first announced (here and/or on GitHub - don’t remember), you might get some insights.

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At time of design I advocated for 12 sliders and alternative names also.

From memory, 8 sliders were chosen not just because of the midi controllers, but also something to do with the guided filter, which only functioned properly (or better?) at 45 degrees, rather than 30. A dev would be able to offer more insight on that.

The slider names came down to individual preference.

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I personally don’t pay a lot of attention to the names. I move the slider and see if the correct part of the picture is being adjusted. Changing the names won’t improve my edits.

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I agree with this. Often, different lighting condition can change our perception of what is green or yellow, etc.

I just find it a little weird that darktable generally is on the side of technical accuracy, but chose pretty inaccurate names for the hue nodes.

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