2009

Thumbnails of photometric web files
The bright red outline shows the beam. For some webs, a darker red outline shows
the (less bright) field.
Photometric Web
The photometric web is a three-dimensional representation of the light
distribution. It extends the goniometric diagram to three dimensions, so that
the dependencies of the luminous intensity on both the vertical and horizontal
angles can be examined simultaneously. The center of the photometric web
represents the center of the light object.
The luminous intensity in any given direction is proportional to the distance
between this web and the photometric center, measured along a line leaving
the center in the specified direction.
5032 | Chapter 18 Lights and Cameras