For minor adjustments and color-correction, the Photos app is extremely useful, but its capabilities are limited to just the basics. Now, with Mac OS X El Capitan, Apple is opening the door for third-party extensions, meaning we can utilize additional, unique tools when editing pictures in Photos. Don't Miss: Tips, Tricks, & Hidden Features for Mac OS X El CapitanSince all new features require some kind of learning period, here's how to get started with third-party extensions in Photos on...