By Matt Fussell
Creating an image that has some black and white areas highlighted by color is called using selective color. Creating an image with selective color is a popular Photoshop effect that is very easy to do. I have seen many different artists do this method in many different ways. The method I am sharing with you seems to be pretty quick and easy.
Start with the image that you would like use. Duplicate the background layer by right clicking on the layer. Select "Image"->"Adjustments"->"Desaturate" to take the color out of the duplicate layer. Then select "add a layer mask" from the layer palette. Use a soft brush with the opacity turned to 80% to paint the areas that you want colored with the color black. If you make a mistake, you can paint with white to desaturate. Think about color theory, so be sure to highlight colors that make sense to create an artistic image.
The following video illustrates how to use selective color in Adobe Photoshop CS4...