Light Graffiti, London, United Kingdom

A technique known from light art is to project images on to irregular surfaces (faces, bodies, buildings etc.), in effect "painting" them with light. The first time The London Trophy for artistic photography was awarded for a colour photograph was in 1967 for a photograph by John N. Cohen that consisted of a colour portrait blended with a negative of a tulip, created by photographing these projected images.
Technique and equipment
A variety of light sources can be used, ranging from simple flashlights to dedicated devices like the Hosemaster, which uses a fiber optic light pen. Other sources of light including candles, matches, lighter flints, glowsticks, and Poi are also popular.