Adjust the settings

The panel on the right has four pages, picked from the icons on its edge — Presets, Adjustments, Crop & Transform and Masks & Cleanup — and most of the work happens under Adjustments. Each section's heading has an arrow that folds it away. Two buttons sit at the top: Auto Adjust and B&W, which turns the photo black and white or back to color. The sections below them run in this order:

• White Balance — Temp and Tint, or click the eyedropper and then click a neutral-gray pixel in the photo to balance from it. Fastest way out of a yellow room.
• Tone — Exposure, Contrast, Highlights, Shadows, Whites and Blacks. This is where most photos are won or lost.
• Presence — Texture, Clarity, Dehaze, Vibrance and Saturation. Texture and Clarity add bite to fine and medium detail; Dehaze cuts through haze, or adds it at negative values. Vibrance leaves skin alone where it can, so try it before Saturation.
• Curve — a point curve over a faint histogram. Pick the RGB curve or one color channel from the four buttons. Click or drag to add a point, and double-click a point or drag it off the graph to remove it. The Point Curve menu has Linear, Medium Contrast and Strong Contrast to start from.
• Color Mixer — Hue, Saturation and Luminance for eight color bands, Red through Magenta. Pick one of the three from the buttons under the heading to see its eight sliders. On a black and white photo the mixer becomes the B&W Mix: the same eight bands, each setting how light that color turns out in gray.
• Color Grading — four color wheels for Shadows, Midtones, Highlights and Global. Drag inside a wheel to tint that range, and double-click it to clear the tint. Click a wheel to show its sliders, plus Blending and Balance for how the ranges meet.
• Detail — Sharpening with Radius, Detail and Masking, then Denoise. Raise Masking to keep sharpening off smooth areas such as skin and sky.
• Optics — Remove Chromatic Aberration lines up the red and blue fringes along high-contrast edges.
• Vignette — Amount, Midpoint, Roundness and Feather. The vignette follows the crop.
• Grain — Amount, Size and Roughness, for a film look.

With several photos selected, each slider becomes a row of step buttons. They move every selected photo up or down from its own value, and the middle button resets that slider on all of them. The curve and the color wheels work on one photo at a time.

Crop & Transform straightens, crops and turns the photo in 90° steps; the crop is kept when you move to another page.

Three habits that make it faster

• Let the histogram start. Auto Adjust sets the tone sliders from the photo's own histogram, so you begin close and fine-tune from there. Click it at the top of the panel, or on a whole selection from the bar under the grid — each photo is read from its own histogram. Reset, beside the Adjustments heading, puts the sliders back to zero.
• Do one, then copy it. Photos from one shoot share the same light, so one good edit is usually most of the way for the rest. Copy Adjustment from a finished photo and tick the sections to carry, such as Tone and Color Grading but not Crop. Then select the rest of the shoot and Apply Adjustment. LightPhotos remembers which sections you ticked. One good frame becomes the look for the shoot.
• Save a look you reuse. When an edit is worth keeping across shoots, press Cmd+Shift+N to save it as a preset.

Cmd+Z undoes the last change: a slider drag, a reset, a crop, a preset, Auto Adjust or a pasted adjustment. A change made to a whole selection undoes in one step. Ratings, flags, labels and rotation are not undone.

None of this touches the original file. Every slider is an instruction stored in the .lightphotos folder beside your photo, so you can close the app mid-edit, come back next week, or reset the whole photo without any harm done. To change only part of the photo, add a mask. When it looks right, the last step is export.