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Adjustments > Color Dimmer v1.0

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This plugin is all about "dimming" a certain channel, which means desaturating the highest-saturation pixels first and working its way down smoothly. There are also other RGB adjustment algorithms that add fine adjustment.

First, let's look at the menu.


((NOTE)): Default settings should have all X-axis's set to 1.00. This makes the image appear as itself. Apologies, since I'm dealing with limitations in Codelab here.

Red -- X axis -- Adjusts the red channel according to the "dimmer" algorithm.

Red -- Y axis -- Adjusts the red channel according to a standard "levels" type algorithm.

Green -- X axis -- Adjusts the green channel according to the "dimmer" algorithm.

Green -- Y axis -- Adjusts the green channel according to a standard "levels" type algorithm.

Blue -- X axis -- Adjusts the blue channel according to the "dimmer" algorithm.

Blue -- Y axis -- Adjusts the blue channel according to a standard "levels" type algorithm.

Proportional Shift -- Alters the Y-axis levels algorithm so the color shift is proportional to the distance between the current value and the max or min values.

If that's confusing for you (it is!), here's a better explanation. If you use the in-built "levels" plugin in, say, red, it will raise or lower the red channel's value globally. So if you have a piece where one section has a red value of 60 and another section has a red value of 200, the "levels" algorithm will raise them both by a fixed amount. So the 60-red will now be 64-red and the 200-red will now be 204-red. More saturated sections will max out at 255, while all other red channels increase by that fixed amount.

The Y-axis of each part of this plugin will follow this algorithm perfectly. However, if you turn on the "proportional shift" option, the channel will instead increase by a proportional amount. 155-red would increase to 205-red, while 55-red would increase to 155-red, because in both cases it's increasing by half the distance to 255.

If you go in the negative direction, the setting would decrease each by its distance to 0, so for example 50-red would decrease to 25-red, while 100-red would decrease to 50-red.

Combined with the fact that black pixels are ignored on the decrease and white pixels are ignored on the increase, this option gives a smoother color transition.

Now, the X-axis algorithm is more complicated. What this does is "dims" a channel by decreasing the saturation, starting with the most saturated pixels and ending with the least. So your 255-reds and 244-reds are the first to be desaturated, while the 30-reds, etc wait until lower settings. The algorithm is set up in such a way that there are no jagged pixels, so this too is a smooth transition.

Combined together, the two algorithms give a fine adjustment of all three channels. I stuck the controls into a double vector so it's easier to make adjustments without switching between sliders.

It's hard to give examples of this plugin's use because the settings can be subtle. Nonetheless:


Seed Image


"Dimmed" Blue to 38.


Same as above, but "leveled" blue to 0.47


Same as above, but proportional


Unrelated to the above; increased all levels to the max with "proportional" on.


Also unrelated; decreased all levels to the minimum with proportional on, and then dimmed blue to 0.49

Actual Plugin:


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