lenses [1]![click to hear](/images/speaker.jpg)
Lenses are characterized by their focal length (between the optical center and the film), aperture (ratio between the diameter of the lens and the focal length) and angle of view (width of the captured image).
standard lens ![click to hear](/images/speaker.jpg)
Lens that produces an image close to that seen by the human eye.
lens aperture scale ![click to hear](/images/speaker.jpg)
Graduated scale that controls the diaphragm’s opening; it is measured in f-stops and a high f-stop indicates a small opening.
depth-of-field scale ![click to hear](/images/speaker.jpg)
Scale that shows the zone of sharpest focus around the subject; this is a function of the diaphragm’s opening and the distance between the lens and the subject.
distance scale ![click to hear](/images/speaker.jpg)
Scale that shows the distance between the lens and the subject on which it is focused.
bayonet mount ![click to hear](/images/speaker.jpg)
Device for attaching the lens to the camera body by fitting lugs located on the lens into grooves on the camera and turning.
focus setting ring ![click to hear](/images/speaker.jpg)
Setting ring that sharpens the image of a subject.
lens ![click to hear](/images/speaker.jpg)
Transparent optical disks through which ambient light enters; the disks correct each other to improve the quality of the image.