Lets get the technical definition out of the way first. Mostly because although correct, reading it just confused the heck out of me. So without further adieu, here is the definition in most photography books: A film plane is the area inside any camera or image taking device with a lens and film or digital sensor upon which the lens creates the focused image.
Camera manufacturers deem this do important that they have even put a focal mark on the camera. Usually on the top or the camera near the mode dial. It looks like a circle with a line through it. That is called the focal plane on today’s digital DSLR models. It is also sometimes referred to as the image plane, sensor plane or film plane in the old days.
This mark is used to calculate the minimum focusing distances on lenses. This is really most useful for macro photographers that need a precise distance and it make the calculations much easier. This is also useful in shooting action where you want to freeze the subject, have it tack sharp, and the background blurred. In order for this to occur, the film plane must be moving at the same speed as the subject otherwise it will not be in focus.
Share this Post