Graphics Programs Reference
In-Depth Information
Site Lighting Analysis
Revit MEP can calculate the average estimated illumination of a Space
object by using the data from the photometric web file associated with a
lighting fixture, but only because the Space object has a volume. Exterior
lighting levels cannot be calculated. Most exterior lighting calculation
applications are able to import CAD data, so you could export your model to
CAD and use the file in your analysis software.
You can, however, use Revit MEP for visual analysis of your site lighting
layout. Lighting fixtures that contain photometric web files can display the
pattern of light emitted from the fixture in renderings. Creating exterior
renderings of your project will give you an idea of the coverage of your
lighting fixtures on the site. This can help you determine whether you are
using the right type of fixture or whether you need to adjust the number of
fixtures used or the spacing of fixtures.
To see the exterior lighting in a rendered 3D view, you need two things. You
need to have a surface upon which the light shines, and you need fixtures
that contain a light source. If you are using a 2D CAD file for your site plan,
you can place a dummy surface at ground level to act as your site surface.
Your 3D view should be set with a nighttime sun position so that the sun
does not interfere with your lighting. You can display the sun position by
using the Sun Settings options on the View Control Bar, as shown in
Figure
12.19
.
Figure 12.19
Sun Settings tool
When you turn on the sun path, you may see a dialog box with options for
displaying the sun path based on the sun settings defined in the Graphic
Display Options settings of the view, as shown in
Figure 12.20
.
