Field guide

Photo mosaics explained

This board does not make mosaics, and this page is not a description of a feature on it. A photo mosaic uses small photographs as coloured tiles that collectively form a larger target image, and it succeeds at two viewing distances for two different reasons — here is what that costs to do properly, so that a tool claiming to do it can be judged.

At close range each tile needs enough pixels to remain recognisable. At distance its average colour and brightness must serve the larger subject.

A larger source library reduces repetition and improves matching. Reusing a strong face or bright object too often creates a visible pattern unrelated to the target.

Colour adjustment can make a tile fit, but heavy tinting defeats the promise that the small photographs remain visible. Limit the correction and accept some local mismatch.

Choose tile count from output size, not ambition. Thousands of cells in a small web image collapse into texture and waste both processing time and source detail.