[Brightcolours]

A much easier way, I find (because the colour(band) selection is so much more precise), is the "Image/Adjustments/Replace Color..." function from Photoshop. With the color dropper and the +/- dropper tools you can get a very precise selection, and you get great feedback when you desaturate and/or change hue. You can make a simple lasso selection over the part where you want to address a certain colour artifact.