2011

Intensity/Intensity Factor
Sets the intensity or brightness of the light. The range is 0.00 to the maximum
value that is supported by your system.
Hotspot
Specifies the angle that defines the brightest cone of light, which is known to
lighting designers as the beam angle. This value can range from 0 to 160
degrees or the equivalent values based on AUNITS and AUNITS.
Falloff
Specifies the angle that defines the full cone of light, which is also known as
the field angle. This value can range from 0 to 160 degrees. The default is 50
degrees or the equivalent values based on AUNITS and AUNITS. The falloff
angle must be greater than or equal to the hotspot angle.
Status
Turns the light on and off. If lighting is not enabled in the drawing, this setting
has no effect.
Photometry
Photometry is available when the LIGHTINGUNITS system variable is set to
1 or 2. Photometry is the measurement of the luminous intensities of visible
light sources.
In photometry, luminous intensity is a measure of the perceived power emitted
by a light source in a particular direction. Luminous flux is the perceived
power per unit of solid angle. The total luminous flux for a lamp is the
perceived power emitted in all directions. Luminance is the total luminous
flux incident on a surface, per unit area.
Intensity Enter an intensity value in candelas, the perceived power in a
luminous flux value, or illuminance value for the total luminous flux incident
on a surface.
■ Candela (symbol: cd) is the SI unit of luminous intensity (perceived power
emitted by a light source in a particular direction). Cd/Sr
■ Lux (symbol: lx) is the SI unit of illuminance. Lm/m^2
■ Foot-candle (symbol: fc) is the American unit of illuminance. Lm/ft^2
Enter f to specify the perceived power in a luminous flux value.
If you enter i, you can specify the intensity of the light based on an illuminance
value.
The illuminance value can be specified in either lux or foot-candles. Enter d
to specify a distance to use to calculate illuminance.
818 | Chapter 7 F Commands