Hello, I just finished helping a friend of mine with a shoot and the DP on set had two tools with him. One being a light meter and the other one I couldn't figure out what it could be. He would take a reading with the light meter then he would take this tool out of his pocket and a green light would flash and then he would look at it, then adjust the film camera. I thought it could be a pocket camera but I have never seen it before. Just looking to see if anyone knows what this might be.
Thanks,