Posterizing reduces a scene to a few flat values so you can read the light-and-dark design — the notan — without detail. It is a planning tool, not a finished style: use it before a painting, or to check whether your completed work still has the structure you intended.
When posterizing helps
- Planning a studio painting from a reference photo
- Checking a master painting’s value structure
- Comparing your finished painting to an early notan sketch
- Simplifying a busy outdoor scene to seven or fewer shapes
Core workflow
- Convert the image to grayscale first — color misleads automatic posterize tools.
- Run posterize at 3, 4, or 5 levels and judge from a distance: does it still look like the scene?
- If software picks wrong values, repaint the poster manually with four swatches from your value scale.
- Always posterize again from the full grayscale original, not from an already posterized file.
Software steps
Photoshop
Image → Mode → Grayscale. Image → Adjustments → Posterize → enter level count (try 3 first). Save a JPEG copy for your notes.
GIMP (free)
Colors → Desaturate. Colors → Posterize → set levels to 3–5. Export as JPEG.
Paint.NET (free, Windows)
Adjustments → Black and White, then Adjustments → Posterize. Same level counts as above.
No editor? Many cameras shoot black-and-white JPEGs — weaker than posterize, but still useful on the LCD before you paint.
Tips for cleaner results
- Shrink the image to roughly 480 px wide before posterizing — fewer tiny shapes.
- Apply a slight blur if the photo is very sharp and noisy.
- Number each shape on the poster (text tool) to match your painting plan.
Trust your eye over the filter
Automatic posterize sometimes makes a sunlit wall too dark or a shadow too light. Squint at both versions: the manual four-value repaint is often more believable than the software default. That judgment is the skill you are building.
Try it at home
Photograph four different subjects (room corner, still life, tree, street). Grayscale and posterize each to nine values. Print or annotate value numbers on the shapes. Keep the set for the next time you plan a painting.
Common questions
- Posterize vs grayscale? — Grayscale keeps all values; posterize forces a few flat steps for design.
- How many levels? — Three for bold design; four or five for most landscapes; nine for study.
- Finished Module A? — Return to the full values guide for the curriculum and upcoming lessons.
Share a posterized study for feedback
Get free art feedback Complete Drawing Guide