Dimming button
A dimming button (formerly also dipping lever ) is a control element of many single -lens reflex cameras . It is used for visual control of the field of focus (also called depth of field ) before taking the picture and, with some cameras, for measuring exposure with the working aperture. More modern SLR cameras only close the aperture on the lens for the recording itself to the value set on the camera ("working aperture"), otherwise the aperture remains fully open ("setting aperture"). This makes the viewfinder image brighter and makes it easier to focus . However, the depth of field of the viewfinder image does not correspond to that of the picture. In order to still be able to check the depth of field before taking the picture, the aperture button can be used to temporarily switch to the working aperture. The viewfinder image becomes darker and an area previously perceived as blurred can be seen in front of and behind the focused object.
See also
Web links
- A look at the depth of field . (PDF file; 104 kB)
- Depth of field with pictures