What is a Film Plane Indicator?

The Film Plane Indicator is a small symbol on your camera that looks like a circle with a line drawn through it. If you were to cut your camera in half, exactly in line with the line through the circle, you would see that it cuts right through at the front of your camera’s sensor. Obviously the naming is a leftover from the days of film, and sometimes you’ll hear it called the Sensor Plane Indicator these days, or the Focal Plane Indicator.

Why do you need to know where the front of your sensor is?  Usually this is used in film production so that focus pullers can mark out exact distances for actors to be from the sensor. For example, if they put a ‘mark’ on the floor 10ft from the Film Plane Indicator, they know that if they set the focus of their manual focus cinema lens to 10ft and the actor “hits their mark”, they will be in perfect focus.

You’ve likely herd the term “hit the mark” before, so now you know that these things are all linked together!