I tweak individual colors, including increasing or decreasing saturation, by using the
Selective Color adjustment. I use Photoshop 7 and it may be available in programs like Paintshop Pro, perhaps called a different name. I do not think this tool is available in Adobe Elements.
I can use a selective color adjustment layer and adjust indiviual colors across an entire image. Or, I can make a duplicate of the original, select an area and make a more localized Selective Color adjustment to a color.
The selective color adjustments, according to Adobe, "consist of the primary additive and subtractive colors plus whites, neutrals, and blacks."
It sounds complicated but it's quite easy to use once you get the hang of it. It is one of my favorite editing techniques.
For example, if I have a photo where the sky is white and washed out, I can change it to blue. This may involve erasing other white areas of the top layer, but this too is easy in most photos.
Or if I want the grass to look a tad more saturated, but not other colors in a photo, I can tweak just green.
(note to self: when are you going to get the Selective Colors tutorial up at the site that you've been meaning to do for months!?!

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