If you want to get all Ansel Adams and start exploring black and white photography, you could go out and buy a fancy photo editing program like Adobe Photoshop, you could go see if anyone still makes film cameras with black and white film, or you could go the super easy and cheap route and just use Preview, an app that’s already on your Mac.
Your call, of course, but here’s how to get Preview to make your photos all arty and stuff.