Move Your Apple Photos Library With a Simple Setup
For better or worse, the new Apple Photos app automatically configures itself using your previous iPhoto settings (if you had them). It can be a little confusing if you need to move something. Luckily, How-To Geek shows you how to change the location of the library.
All you have to do is open Photos and go to Settings> General. Select the Show in Finder option, and then move your photo library anywhere. If you’ve used iPhoto before, synced your photo library with a third-party cloud service, or just needed to move it, this is a pretty easy way to do it. Go to How-To Geek for more information, as well as guidance on how to create your new library in general.
How to Move Apple Photos Library to Another Location | How-To Geek