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LOGEXPDAYLIGHT
Controls if the exterior daylight flag is enabled when using photometric
lighting.
LOGEXPMIDTONES
Controls the mid tones level of the viewport when using photometric lighting.
LOGEXPPHYSICALSCALE
Controls the relative brightness of self-illuminated materials in a photometric
environment.
Illuminate a Scene
You can add point lights, spotlights, and distant lights and set the location
and photometric properties of each.
You can use a command to create a light, or you can use a button on the
Lights toolbar or the Lights panel on the ribbon. You can use the Properties
palette to change the color of a selected light or other properties. You can also
store a light and its properties on a tool palette and use it again in the same
drawing or another drawing.
Guidelines for Lighting
The guidelines for lighting used by photographers, filmmakers, and stage
designers can help you set up the lighting for scenes.
Your choice of lighting depends on whether your scene simulates natural or
artificial illumination. Naturally lit scenes, such as daylight or moonlight, get
their most important illumination from a single light source. Artificially lit
scenes, on the other hand, often have multiple light sources of similar
intensity.
Natural Light
For practical purposes at ground level, sunlight has parallel rays coming from
a single direction. The direction and angle vary depending on the time of day,
the latitude, and the season.
In clear weather, the color of sunlight is a pale yellow: for example, RGB values
of 250, 255, 175 (HSV 45, 80, 255). Cloudy weather can tint sunlight blue,
shading into dark gray for stormy weather. Particles in the air can give sunlight
2150 | Chapter 44 Add Lighting to Your Model