Photography in bubble and drop research

Abstract Methods of photographing bubbles and drops moving in a liquid field are described. Shape, size, terminal velocity, local semi‐vectorial velocities, size distribution and high speed phenomena such as coalescence and breakup can be advantageously investigated by photographic methods. Recommended combinations of lights, reflectors, diffusers, screens, films, and f ‐stop values are given. Applications of particle trace and interrupted particle trace photography are described.