# Four inks, four angles, and a face slightly out of step

> A colour halftone is four dot screens — cyan, magenta, yellow, black — each at its own angle. Knock them a few millimetres out of line and a portrait turns into a pop-art print.

September 25, 2026 · https://justog.club/stories/cmyk-halftone-pop-art-portrait

A cream tee on a dress form in a shop window. On it, a school-photo grin: buzz cut, round cheeks,
a gap between the front teeth, a striped polo collar. It's printed in four colours of big visible
dots, and the colours don't quite line up — a cyan edge down one side of his head, a magenta one
down the other. Underneath, in heavy capitals: RONNIE.

Nobody lined those layers up badly by accident. The slip is the style.

## How does a colour halftone work?

With four separate dot screens — cyan, magenta, yellow and black — printed one on top of another.

Each ink gets its own halftone, sized to how much of that colour is in each part of the picture.
Where they overlap, the eye mixes them: cyan and yellow dots side by side read as green, magenta
and yellow as orange-red, all four as a deep near-black. Every colour photograph in a magazine was
made this way. Up close it's four patterns of dots in four colours; from a step back it's a face
in full colour.

## Why are the dot screens at different angles?

So they don't collide into a pattern of their own.

Lay two identical grids of dots on top of each other at nearly the same angle and they produce a
wobbling interference pattern — moiré — that has nothing to do with the picture. Printers rotate
each colour's screen to a different angle so the four grids interlock into small flower-like
clusters called rosettes instead. Enlarge a colour halftone and the rosettes are what you see:
the texture that says *this is printed* more loudly than any single colour could.

## Why does misregistration look good instead of wrong?

Because it shows the four layers were four layers.

On a press, *registration* means the colours landing exactly on top of each other. When they
don't, a thin fringe of one colour shows along the edge of a shape — cyan on one side of a face,
magenta on the other. In a magazine that's a flaw. Blown up to chest size and done on purpose, it
turns a photograph into a print that visibly came off a machine, which is much of the appeal of the
pop-art portrait. The offset has to be deliberate and consistent; random smears read as damage.

## What kind of portrait suits it?

A face that's already a little bit iconic in its own framing — straight on, strong shadows,
something worn that has a shape.

Sunglasses, a hat, a wide collar, a gap-toothed school-photo grin, hair with a silhouette: the
four-colour treatment exaggerates whatever is graphic about a face and flattens whatever isn't. It doesn't need to be a
famous face. It needs to look like it *could* have been on a poster, which is a property of the
lighting and the pose far more than of the person. A photo of a friend taken with that in mind
does the job.

## Can I use a famous face or a famous pop-art work?

The style is free; the faces and the specific artworks aren't.

Four-colour halftone, rosettes, deliberate misregistration — those are printing methods and
nobody owns them. A particular celebrity's likeness is theirs to license, and a specific
well-known artwork has an owner even when it was made from somebody else's photograph. If that
exact face or work is the point, the permission is part of the job. Usually it isn't: the look is
what people are after, and a friend, a grandparent or an invented stranger in sunglasses gets the
look without the paperwork.

## How is this different from comic dots or a one-colour halftone?

It's the colour version of the photographic halftone, and it sits between the two.

A one-colour halftone is a newspaper photo: [black dots describing light](/stories/what-is-a-halftone-shirt).
Comic dots are [all the same size and make flat tints](/stories/ben-day-dots-vs-halftone). The
four-colour portrait keeps the halftone's changing dot sizes and adds colour mixing and rosettes,
which is why it reads as *magazine* or *gallery print* rather than *front page* or *comic*.

## Does it print well?

Yes, provided the dots are coarse and the four colours are chosen to be seen.

Magazine rosettes are far too fine for cloth — they'd fall [below the grain of the weave](/stories/bold-shapes-survive-fabric)
and blend into a muddy wash. On a shirt the screen is enlarged until each dot is visible from arm's
length, which is also what makes the rosettes and the offset readable. Cream and white shirts
suit it, because the four inks mix against a light ground the way they did on paper, and the
bare cloth between the dots becomes the highlights.

## How do I get one made?

Bring the portrait to [JustOG](/) — ask for a four-colour halftone with the layers slightly out of
register, and say whether a name goes underneath.
Pick a direction, drag the crop frame, see it composited on the real garment, and it's made to
order and shipped.

Designs other people have published are in the [shop](/shop).

Four colours, never quite agreeing about where his face is. That's how you know it was printed.