There are lots of ways to convert color images to black and white. In Photoshop, you can use a grayscale mode change, or convert the image to L*A*B color and then extract the Luminance channel. Or, you can pull a single RGB channel, drain the saturation out of an image or use Photoshop’s excellent Black and White conversion tool. The list goes on and on, but in my opinion, the best way to perform black and white conversion (more accurately called grayscale conversion is with nik’s Silver Efex Pro 2, a plug-in for Photoshop, Aperture, and Lightroom.
The secret to good grayscale conversion is control. You want to be able to precisely alter the tone of very specific colors in your image, and no conversion option offers as much control as Silver Efex. For a detailed exploration of the new version – and why you should order up a copy immediately – check out my full review.