If you run Photoshop, the way I do it is to edit the image all I want, go to the history palette, take a Snapshot of the current state, desaturate the image, and then use the Art History brush to paint on what you want to colorize...it gives you a lot of control over the brush and the location of where you want it to go.
You can also get more control over your desaturated version if you play with the Channels palette, in which you can select the various RGB channels...giving you different feeling B&W images.
Edit: here's an example of something I did with my method in Photoshop CS1
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You can also get more control over your desaturated version if you play with the Channels palette, in which you can select the various RGB channels...giving you different feeling B&W images.
Edit: here's an example of something I did with my method in Photoshop CS1
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