Step Back Yourself

When a wall becomes a picture

Close up, each tile is a thing to read: letters, a logo, a colour. The tree is drawn by something slower — which tiles are darker — and it only becomes a shape once enough tiles are in view for that slow change to outweigh the fast one from tile to tile.

Where that happens depends less on you than on the picture and the screen: how big your screen is, how far away you sit, how much of the tree was in the first view. That is why the answers above are spread out, and why none of them is the right one.