How to paint with sumi ink on the computer

To paint with sumi ink on a computer, use Easel by Zaweba, a free painting studio for Windows. Grind the sumi ink on the stone (the longer you grind, the darker the ink), choose rice paper as your surface, and paint with a brush. Rice paper is fibrous, so the ink bleeds along its fibres much as it does on real paper. There is also a sumi ink preset to start from.

Sumi ink painting, known in Japan as sumi-e, is built on a few elements: black ink, water, a soft brush and absorbent paper. The art is in how much water the brush carries and how quickly and surely the stroke is made. Easel simulates the parts that matter.

Tablet or mouse

Easel, and ideally a pen tablet. Easel reads pen pressure from a tablet when one is attached, which helps a brush stroke swell and taper. A mouse works but gives a steadier, less varied stroke.

Grinding, choosing and painting

Begin with the sumi ink preset, one of the 28 built in, if you want a ready setup. Otherwise choose the pieces yourself.

Pick the surface. Rice paper is the natural choice, and Easel added it in version 1.1 along with parchment and papyrus. Fibrous papers such as rice paper bleed along their fibres, which gives sumi strokes their soft, living edge.

Grind the ink. In Easel, as with a real ink stick on a stone, longer grinding makes darker ink. A short grind gives a grey ink for distant hills and soft shapes; a long grind gives a deep black for accents.

Choose the brush. Easel's round brush is the usual sumi shape. The mop, hake and rigger added in 1.1 are also useful: a hake for broad washes, a rigger for long thin lines such as grasses or bamboo leaves. Brushes come in sable, synthetic and hog hair.

Paint with purpose. Brushes carry a limited load and run dry. By default each stroke dips a fresh load, but you can untick Dip each stroke to let the brush run dry across strokes, which gives the dry, broken strokes known as flying white.

Tone, timing and empty space

Use more than one ink tone. Grinding a light ink for the first layer and a darker ink for the accents gives depth. Ink wash, which Easel also provides, is another way to lay grey tone.

Mind the drying time. Wet strokes that touch will merge; strokes laid over dry ink stay separate. The drying speed slider runs from 0.25 to 4 times, and Dry now locks wet paint in place when you want a clean second layer.

Keep the canvas flat. Tilted wet paint runs downhill, which is rarely what you want in ink painting. Ctrl+0 lays the canvas flat.

Check the composition. Sumi paintings depend on empty space as much as on strokes. The mirror view and squint view, which never change the picture, are good ways to see whether the balance works.

Other inks and papers to try

If rice paper feels too wild, try hot-pressed watercolour paper or cartridge paper, which hold a stroke more crisply. Other inks are on hand too: India ink for strong black line, walnut ink for warm brown, acrylic ink for colour. A calligraphy broad nib, whose line width follows the stroke angle, is there if you want to add lettering in the Western style.

Keeping the session

Save as .zeasel to keep the session, including the time-lapse, which is a lovely record of a brush painting being made. Export to PNG, JPEG or TIFF at 1x or 2x when the picture is done. Easel works offline, so you can practise as often as you like without wasting a sheet of paper.