9

1372 Chapter 15: Lights and Cameras
When you rename a target camera, the target
is automatically renamed to match. For
example, renaming Camera01 to Rolli causes
Camera01.Target to become Rolli.Target.The
target’s name must have the extension .Target.
Renaming the target object does not rename the
camera object.
Clickingthelinethatconnectsthecameraand
its target selects both objects. However, region
selection doesn’t recognize t he link line.
Ifatargetcameraisalreadyselected,youaddits
target to the selection by right-clicking the camera,
and t hen cho osing S elect Target from the quad
menu > Tools1 quadrant. Or you can hold down
the
Ct rl key and click the target to add it to the
selection set.
Using Cameras
Characteristics of Cameras
Real-world cameras use lenses to focus the light
reflected by a scene onto a focal plane that has a
light-sensitive surface.
Real-world camera measurements.
A: Focal length
B: Field of view (FOV)
Focal Len gt h
The distance between the lens and the
light-sensitive sur face, whether fil m or video
electronics, is called the focal length of the lens.
Focal length affects how much of the subject
appearsinthepicture.Lowerfocallengthsinclude
more of the scene in the pic ture. Higher focal
lengths include less of the scene but show grea ter
detail of more distant objects.
Focallengthisalwaysmeasuredinmillimeters.A
50mmlensisacommonstandardforphotography.
A lens with a focal length less than 50mm is called a
short or wide-angle lens. A lens with a focal length
longer than 50mm is called a long or telephoto lens.
Fi eld of View (FO V )
The field of view (FOV) controls how much of the
scene is v isible. The FOV is m easured in deg rees of
the horizon. It is directly related to the focal length
of the lens. For example, a 50mm lens shows 46
degrees of the horizon. The longer the lens, the
narrower the FOV. The shorter the lens, t he wider
the FOV.