Autodesk LIGHTSCAPE, Manual

Page: 207 / 362

Controlling Analysis Grids
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Maximum and Minimum
Displays the maximum and minimum values of the
target quantity over the selected surface.
Use these values in conjunction with the average
value to describe the uniformity of the distribution
of light over the target surface.
Avg/Min, Max/Min, and Max/Avg
Displays different ratios of the average, minimum,
and maximum values. These three ratios are used in
conjunction with the average value to roughly
measure the uniformity of the distribution of light
over a selected surface.
Using I lluminance Rating
The illuminance rating is the fraction of the area of a
surface that satisfies (or exceeds) a specified crite-
rion. You can use this option to obtain more
information about the distribution of light over a
selected surface.
To select i lluminance rating criterion:
1.
Choose Light | Analysis.
The Lighting Analysis dialog appears.
2.
Click the Display tab.
3.
Select an item from the Quantity list.
4.
Click the Statistics tab.
5. Click a point on a surface in your model.
Yellow crosshairs mark the selected point, and the
selected surface is highlighted in green.
6.
Enable the Percentage option in the Illuminance
Rating section, and then type a value between 0 and
100 in the Percentage box.
7.
Enable the Threshold option.
The threshold energy level appears in the Threshold
box.
For instance, in the previous example, 46.4% of the
light energy exceeds 300 lx.
Note:
Alternatively, you can enter a threshold
value and then enable the Percentage option to
see the percentage of surface area where energy
exceeds the specified threshold.
Controlling Analysis Grids
You can display a grid of uniformly spaced sample
points and their corresponding luminance or illumi-
nance values for a selected surface.
The Precision, Origin, and Spacing parameters
control the grid’s position and lighting.
To display a lighting grid for a surface:
1. Choose Light | Analysis.
The Lighting Analysis dialog appears.
2.
Click the Display tab.
Threshold option
Percentage option
Threshold box
Percentage box