why would you need to synchronize those cameras at all? Let them start at random times. Light is supposed to go in one direction, so you can tell which picture

why would you need to synchronize those cameras at all? Let them start at random times. Light is supposed to go in one direction, so you can tell which picture were shot ealier by comparing how far the light beam is. Of course sorting billions of pictures would require some form of Machine Learning (or really large number of interns)