單眼的d是什麼意思

"D" in the context of a single lens reflex (SLR) camera typically stands for "diaphragm" or "aperture." It is used to control the size of the aperture, which is the opening in the camera lens through which light passes to enter the camera body. The aperture controls the amount of light that reaches the camera's sensor and also affects the depth of field, which is the area of the image that appears to be in focus.

On many SLR cameras, the "D" mode on the mode dial is used to indicate aperture-priority mode, which allows the photographer to set the aperture while the camera automatically adjusts the shutter speed to achieve the correct exposure. In this mode, the photographer can control the depth of field by choosing a larger or smaller aperture, while the camera ensures that the image is properly exposed.