Flatting
Flatting is the colouring stage where every region of a comic panel is filled with a single solid colour, with no shading, so that later rendering can select any area with one click. The result is a flats layer used as a selection mask.
What the flats layer is for
Flats are not a first pass at the colours. They are a selection tool that looks like colours. Every discrete region — this sleeve, that hair, that wall — gets its own flat, hard-edged, fully opaque area. Once that exists, a colourist can click any region with the magic wand and instantly have a perfect selection to shade inside, for the rest of the book.
This is why the flats themselves are often garish. Some studios flat in deliberately hideous, maximally distinct hues so that adjacent regions can never be confused, then recolour the whole layer in one pass afterwards.
Two properties are non-negotiable:
- No anti-aliasing. Soft edges mean the wand selection leaks or leaves a halo. Flats are drawn with a hard-edged tool, aliased.
- No gaps. Every pixel under the art belongs to exactly one flat. A single unfilled pixel between two regions is a leak waiting to happen.
Why studios split it off
Flatting is slow, entirely mechanical, and requires no colour judgement whatsoever. Rendering is fast, creative and requires an experienced eye. Separating them means the expensive colourist never spends three hours lassoing hair, and — because flatting needs nothing from the rendering stage — several pages can be flatted in parallel while earlier pages are being rendered.
It is a genuine entry route into the industry: flatting is often the first paid comics job someone gets, and it teaches an enormous amount about how inking is constructed, because you see exactly where every contour fails to close.
Doing it faster
- Close the line art first. Gap-closing is an inking responsibility. If holes exist, patch them on a separate layer above the inks rather than editing the art.
- Work below the line art, on a layer set behind it, so the ink stays crisp on top.
- Lasso, then fill. For hair and complex shapes the polygonal lasso is faster than chasing the wand; fill inside the selection and clean the boundary once.
- Expand every fill by 1–2 px under the line art. Filling exactly to the edge leaves white fringing when the ink layer is later thinned or the image is scaled.
- Flat the largest area last and simply fill everything remaining — the background is usually whatever is left.
When you can skip it
On a solo project with soft, painterly rendering and no hard region boundaries, flats buy little. They pay for themselves when there is a team, when the same characters recur across many panels with a fixed palette, or when the work is long-form colour — a webtoon series with weekly episodes is precisely the case flatting was invented for.
Related terms
- Inking Inking is the stage where a comic's pencil drawing is redrawn in permanent black line. The inker decides which edges become lines, how thick each line is, and which areas are filled solid black — the choices that give a page its depth and contrast.
- Line weight Line weight is the thickness of a drawn line, varied deliberately across a piece of art. Thicker lines advance towards the viewer and read as shadowed or heavy; thinner lines recede and read as lit or delicate, which is how flat line art conveys depth.
- Panel A panel is a single framed image in a comic that shows one moment of the story. Its border marks where that moment ends, its size controls how long the reader spends there, and the sequence of panels is the sequence of time.
- Screentone Screentone is a sheet of pre-printed dots, lines or gradients applied to black-and-white comic art to produce grey values. Originally adhesive film cut with a blade and burnished down, it is now nearly always applied digitally as tone layers.