six colors.com has a nice post on the latest version of Photos for Mac. I noticed one thing that surprised/disappointed me (in bold): - Support for third-party edits. In the transition from iPhoto to Photos, the ability to edit a photo in an outside app and then save it back into your photo library was lost. It’s back now, and it’s better than it ever was in iPhoto. In Photos on High Sierra, you can open any photo in an external image editor via the Edit With command under the Image menu. Under the Edit With menu will be a list of all the apps on your Mac that have been updated to take advantage of this feature of Photos, meaning you don’t need to pick a single external editor—you can choose different apps as you see fit. Once an image has been opened in an external editor, you can do pretty much anything you want to it. Once you save in the app, the adjustments you’ve made come back to Photos right where you left it. You can make further edits on that photo if you want, and as with any photo in Photos, the original image is stored so you can revert back at any time. One caveat: If an image is shot in the Raw file format, the Raw file is not sent to the external editor; instead, a JPEG version is transferred. (The Raw original is always saved and can be reverted to later, of course.) Is he correct?