saturation/vibrancy mask action

[lutz]

The attached action creates a saturation mask and allows to regulate the blending of layers according to the saturation values of the active layer.
As shown (exaggerated) in the example below, this allows any image changes to be restricted to certain saturation levels.

The masked out saturation ranges are determined by the "false color" working layer in the saturation mask layer group.
To mask out low saturation ranges, the left part of the gradient should be assigned black false colors. To mask out highly saturated regions the brighter right part of the gradient shold be assigned a black false color.

Saturation changes determined by the saturtion levels of the original file (thanks to Siilur ; morguefile.com):


Some photoshop tutorials on the use of saturation masks.
http://www.goodlight.us/writing/saturat ... -mask.html
http://www.goodlight.us/writing/saturat ... ation.html
http://www.luminous-landscape.com/tutor ... pped.shtml

As far as I understand, Tony Kuiper uses the term "saturation mask" in the case where the saturation is directly translated into a mask-layer (for this, the false-color working layer generated by the attached action can be deleted). Tony's "vibrancy mask" (masking out only highly saturated regions) should be equivalent to the mask generated by default by this PhotoLine action .
The attached action does not introduce any image changes by itself - these have to be applied to the active layer before or after running the action.

[Hoogo]

When I've read about the saturation mask it was usually used to saturate the less-saturated parts of a picture more than the already saturated ones. If it's only used for that purpose it can be replaced by a simple histogram-function. In the histogram you can adjust the minimum saturation of the picture just as you would adjust any other channel.

[lutz]

Hello Hoogo thanks for the tip!
To increase the "vibrancy" of the less-saturated parts is certainly the most popular application of saturation masks (there are many other possibilities). I had played around with the histogram tool and gamma adjustments of the saturation channel for this purpose. As far as I understand you are suggesting to increase the minimum output-level. Although the saturation masking and these histogram manipulations should/could produce similar outputs, they do not - in my attempts. The histogram manipulations seem to useful (mostly) for minor adjustments as they quickly introduce artifacts of color-clipped blotches ( red arrows) - Perhaps a fully featured curves tool for the HIS space would be required? In any case it is surprisingly difficult to reproduce results of one method with another. For the standard editing needs the saturation masks tend to produce more realistic effects over here.


Original Image thanks to Siilur (morguefile.com).

When I've read about the saturation mask it was usually used to saturate the less-saturated parts of a picture more than the already saturated ones. If it's only used for that purpose it can be replaced by a simple histogram-function. In the histogram you can adjust the minimum saturation of the picture just as you would adjust any other channel.