Photo Preparation for Photo Mosaics
The quality of a photo mosaic is decided more by the photos you feed it than by any setting. Preparation splits into two jobs: choosing one main image that will survive tiling, and assembling a tile library varied enough to match it well. Both are learnable skills with simple rules.
Choosing the Main Image
One clear subject — the more the image is “about” one thing, the better it tiles.
Strong contrast — subject clearly separated from background in brightness or color.
Simple shapes — silhouettes and large features survive; fine detail does not.
Faces forward and large — for portraits, the face should fill a third or more of the frame.
Decent resolution — the main image is a reference, not a print source, but very small images limit analysis.
Building the Tile Library
Aim for variety across three axes: brightness (dark, mid and bright photos), color (warm and cool), and content (people, places, objects). A library of five hundred similar beach photos matches worse than two hundred mixed ones.
More photos help, but only varied ones. If your archive is one-toned — a year of forest hikes — borrow from friends or older albums to widen the palette.
Practical Preparation Steps
Gather everything first; curate second. Deleting is easier than hunting later.
Remove exact duplicates, but keep near-duplicates — they give the matcher options.
Do not pre-crop tiles to squares; the software crops to the cell shape itself.
Scanned prints are welcome — the era mix makes tiles more interesting up close.
Keep originals untouched; work on a copied folder.
Common Mistakes
A beautiful but low-contrast main image — moody photos tile badly.
A library dominated by one color — the mosaic will drift toward that tone everywhere.
Too few photos for the cell count — repetition controls cannot invent variety.
Over-editing tiles — heavy filters distort matching; near-natural photos match best.