The focusing screen of a SLR camera is easily seen when the lens is removed.
The focus screen on a single-lens reflex (SLR) camera forms a solid surface onto which the subject may be sharply focused. When the shutter is released, the focus screen flips up, allowing the focused light to fall onto the digital sensor (or film when using a film camera). Removing a focus screen is quick and easy, allowing it to be cleaned or replaced. A wide variety of focus screens are available, each providing you with different focusing options.
Instructions
1. Turn the camera power off and remove the main lens from the camera body. The focus screen is the frosted rectangle of glass visible in the back of the camera body. It will be positioned at an angle relative to the film/sensor plane.
2. Lift the spring-loaded retaining clip holding the focus screen in place by grasping the small indentation found along the edge. Depending on make and model of camera, the small indentation is located someplace along the bottom of the retaining clip. The retaining clip will flip out when gently pulled.
3. Lift the rectangular, glass focus screen off of the screen housing using a pair of small, needle-nose pliers and place the focus screen on a piece of clean lens paper. The spring-loaded retaining clip will remain open until you close it. If you do not replace the focus screen, the camera will not be able to focus.
Tags: focus screen, retaining clip, focus screen, camera body, clip will, retaining clip will