Curves, Tone and HSL — the three tools that separate an edit from a filter

The tone curve, split-toned highlights and shadows, and per-colour hue, saturation and luminance. What each one is for, and the order to use them in.

Most edits are made of exposure, contrast and a LUT. That gets you most of the way. The last stretch — the part where a photo starts looking like yours rather than like a preset — is done with three tools sitting further down the Adjust grid: Curves, Tone and HSL.

Curves — brightness, precisely where you want it

A curve is a graph. The horizontal axis is the brightness a pixel has; the vertical axis is the brightness it gets. Leave it a straight diagonal and nothing changes. Bend it and you redistribute light exactly where you choose, which is what makes it different from an exposure slider that moves everything at once.

Three shapes cover most work:

• The S-curve. Pull the lower part down, the upper part up. Shadows get deeper, highlights get brighter, and the midtones stretch out between them. This is contrast, but contrast you aimed.
• The lifted black point. Drag the bottom-left end upward. Blacks stop being black and become dark grey — the matte, faded look of a print, or of film scanned badly on purpose. A tiny lift goes a long way.
• The rolled-off highlight. Pull the top-right end down slightly so the brightest values stop short of pure white. Skies and skin stop clipping and the photo feels calmer.

A practical note on ordering: Curves bakes your shape into the colour pipeline, and choosing a LUT afterwards replaces that colour step. So do it the other way round — pick your LUT first, get your exposure right, and shape the curve last. Treat the curve as the finishing move, not the opening one.

Tone — colour in the light and the dark separately

Tone is split toning. It gives you two colour controls, one biased toward the highlights and one toward the shadows, and it is the fastest route to a look that reads as graded rather than filtered.

The classic pairing is warm highlights with cool shadows — amber light, blue-teal shade. It works because that is how daylight behaves: a warm sun and a blue sky filling the shadows. Push it far and you get the studio blockbuster look. Keep it gentle and it just makes a photo feel like it was taken on a good evening.

The reverse — cool highlights, warm shadows — is worth trying on interiors and on anything shot under fluorescent light. It is less obvious and often more flattering.

Alongside the split-tone controls sit the Highlights and Shadows sliders, which do the brightness half of the same job: recover a blown sky, open up a face that fell into shade. Use those to fix, and Tone to flavour.

HSL — one colour at a time

HSL breaks the image into colour bands and gives each one three controls:

• Hue — nudge the colour itself. A narrow range, deliberately: it is for shifting a green toward olive, not for turning grass purple.
• Saturation — from grey right through to double intensity.
• Luminance — how bright that colour band renders, from half to one and a half times.

This is the tool for problems no global slider can solve. Skin that has gone orange under warm light: pull the orange band's saturation back a touch and lift its luminance. A green that reads as neon: drop the green saturation and shift its hue slightly toward yellow. A sky that is nearly right: raise blue saturation and lower blue luminance — deeper, not brighter, is what makes a sky look good.

The best use of HSL is subtractive. Instead of making a colour louder, quiet the ones you don't want. A photo where only one thing is saturated looks intentional; a photo where everything is saturated looks like a phone did it.

The running order

1. Exposure and white balance — get the frame neutral and correctly bright before touching anything creative.
2. LUT — pick the look, then dial its intensity back to where it flatters this photo.
3. Highlights and Shadows — recover what the LUT crushed or blew out.
4. HSL — fix the one or two colours that are still fighting you.
5. Tone — flavour the lights and darks.
6. Curves — the final shape: the S, the lift, the roll-off.
7. Compare. Press and hold the canvas to see the original underneath, then decide whether step 6 was worth it.

You can do all of it in five taps or spend twenty minutes on one frame. The order is the part that matters — each step assumes the one before it is already right.