|Focal Plane Mark on the Camera Body|
If you pay attention to the top part of your DSLR camera, in the space between the mode dial and the viewfinder you will see a symbol which looks like the Greek letter Phi (a circle with a line through it). Ever wondered what it means? It is called the focal plane mark; also known as image plane, sensor plane or film plane (in the days of film cameras).
What is Focal Plane Mark?
|Focal Plane, Sensor Plane, Image Plane or Film Plane|
Focal plane mark indicates the position of the sensor inside the camera.
What is Focal Plane Mark Used For?
|Focal Plane Mark|
It is from the focal plane mark that distances are to be measured when calculating the minimum focusing distances of lenses. It is very useful to know how close your lens can be to the subject and still focus. This feature is most useful for macro photographers as they often find it necessary to determine the exact distance from the subject to the sensor and having the mark on the outside of the camera body makes their calculations a lot easier and more precise.