Turn continuous tones into a limited palette
Dithering represents intermediate tones with a pattern of coloured pixels or marks. It suits retro graphics and deliberate texture; it is not a detail-recovery filter.
Build a controlled comparison
- Upload an image with a recognisable subject and retain a copy of the original.
- Start with a two-colour result. Choose foreground and background colours with enough contrast.
- Compare ordered Bayer with the available noise patterns. Watch gradients, flat backgrounds and facial edges.
- Adjust levels and spacing one at a time. Inspect at the intended poster size rather than judging only a small thumbnail.
- Export the result, then test-print a gradient and a detailed area before printing every sheet.
Avoid common surprises
Too little contrast between selected colours can make the subject disappear. Dense repeating patterns may produce visible banding or interference when resized or photographed. Compare the exported file at its own scale.
Dithered output is rendered image content, including when placed into a PDF. Do not mistake a PDF container for infinitely scalable vector pixels.