Datasheet
PRINCIPLES OF THE LENS
84.1° 24 mm
18.2° 135 mm
75.4° 28 mm
12.3° 200 mm
46.8° 50 mm
8.2° 300 mm
122° 12 mm
34.3° 70 mm
5° 500 mm
103.7° 17 mm
23.3° 105 mm
3.1° 800 mm
94.5° 20 mm
FISHEYE 180° 15 mm
FISHEYE 180° 8 mm
ANGLE OF VIEW AND FOCAL LENGTH
What you should know to choose the right lens for your needs.
use a faster shutter speed, or more
easily create defocused bokeh eects,
not to mention providing a brighter
viewfinder image. F-stops represent
focal length divided by eective
aperture diameter.
You can control perspective by
moving nearer or farther from your
subject and then choosing a lens
that frames your subject the way
you want. To compress the distance
between foreground and background,
step back and use a telephoto lens
(or zoom in). To spread out the
background and emphasize distances,
get closer and use a wide-angle
lens (or zoom out). The telephoto
isolates your subject, while the wide-
angle lens includes the subject’s
surroundings.
When you focus on a subject, some
objects in front of and behind the
subject will also be in focus. “Depth
of field” refers to the depth of this
foreground-background distance.
A smaller lens aperture (higher
F-stop), increases depth of field,
bringing more foreground and
background into focus. A larger
aperture (lower F-stop) isolates
your subject with a blurred “bokeh”
foreground and background. Focal
length is also a factor. Telephoto
lenses have less depth of field,
wide-angle lenses have more.
Angle of view is determined by the
focal length of the lens and the size
of the image (sensor or film format)
frame. With a given image size,
changing the focal length will change
the area of the scene that appears in
the photographic image. Expressed
in degrees, this area of the scene
is the angle of view, which in this
catalog, is computed in reference
to the diagonal of image formats
measuring 36 mm x 24 mm, 20.7 mm x
13.8 mm and 23.55 mm x 15.7 mm.
The longer the focal length, the
smaller the angle of view and the
greater the image magnification.
The aperture controls how much light
can be gathered by the lens. The
lower the f-stop (F2.8, F4, F5.6, etc.),
the larger the aperture and the more
light it will transmit to the image
sensor. A so-called “fast” lens (low
f-stop at maximum aperture),
lets you shoot with less illumination,
Angle of View
Aperture, F-stops and
Lens ‘Speed’
Depth of Field
Perspective
F22
F2.8
21