Map a portrait into the four tones of a HOPE-style poster

Pick a photograph with a clear side light

Use a consenting sitter photographed near a window. Look for a bright cheek and a shadow beneath the chin. Flat frontal light often merges the nose and cheek into one area, making the next step much harder.

Make the light map before choosing hues

View a grayscale copy and group the values into paper, light midtone, darker midtone and shadow. Trace the largest shapes first. Where the cheek turns away from the light, keep a single clear boundary that follows the form.

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Give each colour a job

Let warm paper carry the brightest forehead, pale blue describe the lit plane, red pick out a middle plane, and navy anchor the deepest features. Use broad shapes to describe a face. The colour assignment is an exercise with your own photograph.

Open up the eye

Zoom out until the head is the size of a thumbnail. If the brow and upper eyelid become one dark bar, carve out a small area of the lighter tone. Check the same detail at full size before altering the second eye.

Set the word after the face reads

For a studio self-portrait, try a short title such as “MAKE”. Put it on a separate band and leave a margin around it. The title should survive a reduction without becoming the darkest feature in the whole face.

Proof the four swatches

Print or display a thumbnail beside the colour study. If two midtones merge, change their brightness and repeat the test. Keep the photograph, four-value study and finished art together so viewers can see how the translation was made.

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