It’s all in the edit
1 Silence Live Photos
Double-click a Live Photo and click Edit to access the editing view. Here, you can use the two buttons at the bottom left of the window to, respectively, turn off the Live Photo (circular icon), or just mute its audio (speaker icon).
2 Trim Live Photos
Below your Live Photo, you’ll see a filmstrip common to video editing apps. Drag the drag handles to trim the Live Photo’s video component. You can also click a frame and then click Make Key Photo to change what’s shown when the image is still.
3 Bounce and loop
A standard Live Photo defaults to the Live option in the menu to the right of the trim controls. But you can switch the animation type to Loop (endlessly repeats) or Bounce (animates back and forth). Use Long Exposure to fake a long exposure shot.
4 Make adjustments faster
In macOS Sierra, editing in Photos was stripped back. On clicking Adjust, only a few options were shown; you had to manually add more. In macOS High Sierra, this has changed. Adjust is a scrolling pane of collapsible sections, all of which are immediately available – and this is far more usable.
5 Explore filters
In all honesty, Photos isn’t necessarily the best place to go if you’re looking for the world’s most amazing filters, but they’ve at least been shaken up a bit in macOS High Sierra. Chrome, Process, Transfer and Instant have all gone, replaced by filters badged Vivid and Dramatic, both of which have Cool and Warm variants.
6 Work with curves
The Curves tool is new to Photos. Click Auto and Photos will automatically improve your image. You can manually drag points, and add new ones by clicking on the curve. Try fashioning a subtle S-curve to make your colours really pop.