The new Adobe Photoshop CC introduced quite a few awesome updates to existing tools and feature. One of the most welcomed ones sure is some of the new Image Resize functionalities, check it out.
Fun, yet very useful tutorial, where you manipulate a photo in a way it will look like you're standing next to Brad Pitt or any other person in that matter.
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.