How to use the depth-of-field preview button on your dSLR - CNET

How to use the depth-of-field preview button on your dSLR CNET It's not the button you press to take the lens off the camera. On most modern dSLRs there is another button that is usually dedicated to depth-of-field preview. Depth of field, or DOF, is the range between areas in an image that look sharp. It's ...