High contrast photography, and how to actually get it

Contrast is the difference between the darkest and the lightest parts of a photograph. That is the whole definition, and almost everything people argue about follows from it. A high contrast image reaches well into both ends, deep blacks and bright whites; it may or may not have much in between. A low contrast one keeps its tones close together — often in the middle, greys against greys, but a low-key or high-key picture can hold a narrow range near the bottom or the top instead.

Neither is better. High contrast reads as bold, graphic and often harsh; it suits strong shapes, hard light and subjects that can survive losing detail in the shadows. Low contrast reads as soft, quiet and atmospheric; it suits fog, skin, and anything where the point is mood rather than shape. The mistake is not choosing one, it is choosing neither and landing in an accidental middle.

Where contrast comes from before you edit anything

Most of a photograph’s contrast is decided by the light, not the slider. Understanding that is what stops you trying to fix in editing what you should have seen when you took the picture.

• •Source size sets how hard the shadow edges are. A small or distant source — direct sun, a bare flash, a single bulb — gives sharp-edged shadows; a large one relative to the subject, like an overcast sky or a big window, gives shadows that fade rather than fall.
• •How dark those shadows go is a separate question, and it is mostly about fill. Light bouncing back off a wall, the ground or a reflector lifts the shadow side and lowers contrast without changing the edge quality at all. Hard light in a white room can be lower contrast than soft light in a black one.
• •Direction changes which surfaces are lit, not simply how much contrast there is. Front light hides the shadows behind the subject so the picture reads flat; side light reveals form and texture; backlight can be higher contrast than either, since the subject may fall several stops below the background.
• •Subject tones set a floor. A dark coat against a white wall starts with a lot of separation built in, though uneven illumination can shrink or even reverse it. A grey cat on a grey sofa starts with almost none, and no slider will invent separation that was never there.

What the contrast slider actually does

Adjusting contrast afterwards is one multiplication. Every tone is pushed away from the middle grey by the same proportion: what was already light gets lighter, what was dark gets darker, and the midpoint stays put. Raising contrast by 20 percent multiplies every tone’s distance from that midpoint by 1.2.

Two consequences fall straight out of that. First, the effect is strongest at the ends and does almost nothing to tones near the middle, which is why a flat, mid-toned photo often refuses to improve no matter how far you push. Second, tones pushed past pure black or pure white have nowhere to go and stop there. How much that costs depends entirely on where the photo already sits: at a factor of 1.2 nothing between roughly 21 and 234 clips at all, and a picture whose highlights are already near the top can lose them while the shadows are untouched. Light does not get a free pass either — a scene whose range exceeds what the sensor can hold loses the ends before you open an editor.

The multiplier is the slider divided by 50, so 60 means 1.2 and 70 means 1.4. For a sense of scale, the presets in this site’s editor sit between 42 and 60. Soft Nostalgia, the flattest, uses 42. Disposable Flash, Flash Pop and Lomo Punch all use 60 — the first two because they imitate hard flash, the third because a punchy toy-camera look wants it. That is the working range for a whole look: roughly a fifth either side of neutral. Much past that and the result starts reading as a graphic rather than a photograph, which is a matter of taste rather than a rule.

Three things that get confused with contrast

Saturation

Raising contrast usually makes colours look more saturated, because pushing tones apart pushes the channels apart with them. It is not guaranteed — clipping and the particular colours involved both change the outcome — but it happens often enough that people then raise saturation as well and land somewhere garish. If a photo looks flat, try contrast first and judge the colour afterwards.

Clarity, or local contrast

Contrast as described here is global: every pixel is treated the same regardless of where it sits. Clarity works on local contrast, boosting the difference between neighbouring areas rather than between the extremes of the whole frame, and texture does something similar at a finer scale. That is why clarity brings out skin and stonework in a way a global slider mostly does not, and why overdoing it produces the crunchy, over-processed look that global contrast rarely manages on its own.

Exposure

Exposure moves every tone the same way — scaling them together, in stops, rather than shifting them by a fixed amount. Contrast moves them apart. An underexposed photo is dark; a low contrast one is grey, and reaching for exposure to fix greyness only gives you a lighter or darker grey.

Contrast is most of what black and white is

In a colour photograph two objects can be told apart by hue alone: a red mug on a green cloth separates cleanly even if both are equally bright. Remove the colour and that particular separation vanishes. Tone is not the only thing left — shape, texture, composition and the channel weighting of the conversion itself all still do work — but it loses a tool it had, which is why so many colour photos look disappointing in monochrome and why a converted picture often wants more contrast than the colour version did.

It is also part of why the classic black and white subjects are what they are. Strong shapes, hard light, deep shadow: all of them are ways of guaranteeing separation. None of it makes low contrast wrong — quiet, close-toned monochrome is a deliberate and very old style, not a failed edit.

When high contrast is the wrong answer

• •Portraits in hard light, unless that is the point. Contrast deepens every shadow, and on a face those are under the eyes and beside the nose. Plenty of portraiture uses exactly that on purpose; it just is not the flattering default.
• •Photos you will print, if you are not soft proofing. Paper holds a narrower range than a screen, so a picture pushed hard on a phone can come back with the shadows merged. Colour management and a soft proof against the actual paper profile handle this; skipping both is what causes the problem.
• •Anything already clipped. If the highlights are blown and the shadows are solid, raising contrast only widens the parts of the picture that contain no information at all.
• •Record shots where the picture has to be believed. High contrast reads as a decision, and on a photo whose job is to show what was there that can work against it. Documentary photography as a genre uses contrast freely; a product shot or an insurance photo should not.

A short working method

1. 1Decide whether the picture wants to be bold or quiet before touching anything. Most disappointing edits come from not choosing.
2. 2Set contrast first, before colour. It changes how saturated everything looks, so judging colour beforehand means judging it twice.
3. 3Watch the ends, not the middle. Push until something you care about is about to clip, then come back a little.
4. 4If the photo is going to black and white, expect to need more contrast than felt right in colour — usually noticeably more.

The contrast control in the editor here sits in the Basic group, starts at 50, and is the same single multiplication described above. If you want to see the effect at its clearest, drop the colour first: with hue gone, contrast is doing a much larger share of the work, and it becomes obvious how much of it you actually need.