Edit
The pass you make at 11pm.
Open a photo and press E. Exposure, colour and tone, with a live histogram, applied to the delivered copy and never to your original.
There is no Apply button. Values are held as you set them and written when you move to the next photo. What the preview shows is what the export writes, because the same renderer draws both.
Read the histogram before the sliders. It sits above the controls and shows the frame as it will deliver. The small squares in its top corners are the clipping warnings, shadows on the left and highlights on the right, coloured by which channels are gone and white when all three are. Hover for the exact percentages.
Hold the backslash key to see the photo before your edits. A before badge appears while you hold it.
The sliders
Tone, Color, Presence
Tone is Exposure, Contrast, Highlights, Shadows, Whites and Blacks, or switch it to Curve for a point curve. Click to add a point, drag to move, double-click or Delete to remove, arrows to nudge. Color is Temp and Tint, with the tracks tinted so you can see which way is warm. Presence is Texture, Clarity, Vibrance and Saturation. Each group collapses, and a collapsed group shows how many of its sliders you have moved.
Pick grey in the Color header is the white balance eyedropper. Arm it, click something neutral in the photo, and Temp and Tint set themselves.
Three ways to set a value. Drag the slider, click the number and type it, or hover over a slider and press the up and down arrows without clicking at all. Hold Shift for larger steps. Double-click a label or its track to put that one slider back to zero.
Auto sets the sliders from this photo’s own histogram, which is a starting point rather than an answer. Level finds a horizon on its own, and Line lets you drag along something that should be level when the frame is too busy for Level to guess.
One frame, then the rest
Copy Edits and Paste Edits
Dial in one photo, press ⌘C, move to the next and press ⌘V. Right-click a selection in Browse and Paste Edits puts the same look on all of them, telling you how many already carry edits it will replace.
This is Copy Edits, not Copy to Folder. It moves the slider values, never the file. The old ⇧⌘C and ⇧⌘V still work if that is what your hands do.
Save a look you keep reaching for with Save current… under Presets, and it is one click on any photo afterwards. Applying a preset fills the sliders for the photo in front of you and nothing else, on purpose: use Paste Edits when you want a run of frames to match.
RAW
Edits are for rendered files
A RAW file opens on the Tag view alone. There is no crop or adjustment pipeline for RAW in Desktop, so the Crop and Edit tabs do not appear on one.