Increased saturation in high ranges of saturation only
Red and blue added to high ranges of saturation only
Wouldn’t it be great if you could selectively adjust colors based on how saturated they are in Photoshop? You can! How? With a free plug-in Adobe provides called Multiplugin; it hasn’t been updated since Photoshop CS5 but it still works with current versions.
Why would you want to do this ?
Do you have images where semi-neutrals not saturated enough, but you don’t want other colors to get too saturated? Select the less saturated colors before adjusting them. Do you have images where you’d like to reduce the saturation of very saturated colors without affecting other levels of saturation? Select the more saturate colors before adjusting them. You can even select colors with medium saturation, separating them from both the high and low range of saturation. Using this technique, you can produce subtle color effects that aren’t possible with any other method.
You might ask yourself, “Isn’t relative saturation adjustment what Vibrance does?” Yes and no. Yes. Vibrance does saturate the less saturated colors more than the more saturated colors and it prevents clipping in the most saturated colors. No. Vibrance offers no control over which ranges of saturation are affected; it can only adjust saturation but not lightness or hue; and it limits how strong an adjustment you can make – it won’t produce effects as strong as Hue/Saturation.
Saturation masks aren’t for saturation adjustments only. This simple selection / mask can be used with any color adjustment tool in Photoshop, greatly expanding your ability to adjust color. Imagine adjusting the lightness and/or hue of high, medium, or low ranges of saturation independently of one another.
Semi-neutrals not interesting enough? Try selecting the low levels of saturation and shifting their hue. Cool them with cyan and/or blue. Warm them with yellow and/or red. Or, try a Renaissance painting technique and add brown.
Throughout the history of photography, most people didn’t think about color this way because they didn’t have the ability to do it. Now you can. It’s well worth your time to explore this new way of seeing, thinking about, and adjusting color.