There are many different techniques and ways of creating a selective color images in Photoshop, let me show you the one where we use the black & white adjustment layer.
Adobe Photoshop CS6 comes with many great features, let me show you how to turn a daylight photo into a photo that looks like it's been taken at evening, sundown or at night with only a click.
If you like the Lords of the Rings movie trilogy, then you might also like this Photoshop tutorial, where we will make a dramatically red sky on a random photograph.