Pedestrian crossings hold people still for 30 to 60 seconds. They cluster, they wait, they look at their phones, they talk. Then they all move at once.

Position yourself at the edge of a crossing. Shoot the waiting. Shoot the release. The moment the light changes and thirty people step off the kerb simultaneously is one of the recurring gifts of street photography.

Watch for: the person who doesn't move with the crowd - the one who hesitates, turns back, goes against the flow. That's usually the picture.

The point: crossings are free stages with a predictable rhythm. Use them.