Install for New Photos Features
Apple delivers major upgrades to the Photos app in macOS High Sierra. if you rely on this to manage your photo library, edit your photos and track faces you need to install High Sierra.
There is a new edit pane that offers more controls to edit your photos faster and make them look better without the need to buy Pixelmator or subscribe to Photoshop. The new advanced editing tools include curves, selective color editing and new professional filters. if you do edit in a third party app, the changes can be saved right back into your photo library.
When you are looking at your library the new sidebar shows you more and offers faster access to what you are looking for in the Photos app. You can also now organize photos easier with a new selection counter and drag and drop functionality.
You can edit Live Photos better using the new Loop, Bounce and Long Exposure features Apple first added to iOS 11. You can now trim mute and pick a key photo for your Live Photo.
Apple also adds in new Memories features like pets, babies, outdoor activities, weddings, concerts and more. When you teach Photos who people are using Face Recognition you will now see it sync across your devices if you use iCloud Photo Library.