For every light in your model, you can edit its properties. You can access the
Properties window by double-clicking the light indicator (see
Object Properties) or by selecting
Lights and clicking
Edit for the desired light.Three pages of a light's properties are specific to lights:
Light,
OpenGL Specific, and
LightWorks Specific.
Lig ht Light Properties
Parameters of the light quality and location.
Light Type: Type and color of the light, and whether it is on or off.
*Power:* The intensity of the light, in watts. The higher the setting, the brighter the light. This parameter is relevant only for
Radiosity rendering. The absolute values (0 through 255) of the color components handled through the
Color controls determine the absolute value of the light power. For example, if only the Red color is enabled and its color value is N (N=R+G+B), then the actual value of the light power is determined by the following expression (P*N/255) where P is the power value set in the
Power field.
Tip:
Setting wattage values too high can cause objects to have a washed-out appearance. *Spot:* Parameters that apply only to
Spot lights - sources that emit light constrained to a cone.
*Penumbra:* The angle of the beam.
*Umbra:* The angle of the dark center of the spot light.
*Beam:* The sharpness of the spotlight. A value of 0 means the light will be evenly dispersed. A higher value means more light will be concentrated toward the center of the beam.
*Sky:* Parameters that apply only to
Sky lights.
*Light distribution:* The level of sky clarity, ranging from clear to overcast. For a clear sky, the brightest part of the sky surrounds the sun. For an overcast sky, the brightest part of the sky is straight up.
*Min Lod:* Minimum level of detail for area source decomposition. Usually this value is between 0.0 and 1.0, closer to 0.0, but values can be greater than 1.0 as well. This parameter determines the initial sampling for lighting calculation. If
Min Lod is too low, shadow boundaries may not be reproduced correctly. If it is too high, rendering may take a long time. Practical values are between 0.0 and 0.5.
M, their values will be reversed. *Temperature:* The ambient temperature, in degrees K. Used to set the sky color. *Er, the shader will perform adaptive sampling, once its initial sampling is complete. The *Error bounds parameter then dictates the accuracy of the solution. An value of 0.1 means that the maximum error associated with the illumination of a particular point of interest is less than 10% of the energy associated with the illumination arriving at the point. Values much smaller than 0.1 are not unusual; the default value (0.5) discourages adaptive sampling.
*Noise factor:* You can add noise to provide patterns which look naturally chaotic and noisy. A value of 0.0 means no noise; a value of 1.0 means maximum noise.
Position: The location or origin of the light.
Direction: For lights with a specific orientation, these are delta values in X, Y, and Z representing the directional vector.
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Parameters relevant for OpenGL rendering.The Open GL rendering engine creates views of lower quality than the LightWorks engine, but at a higher speed. 
Ambient: The amount of ambient light - light provided equally from all directions. *Dif
fuse:* The quantity of diffuse light reflected by each surface that is lit by the light. When diffuse light strikes a surface, it is reflected in every direction equally. This makes the surface appear as if it has a rough or matte finish.
*Specular:* The quantity of specular light reflected by each surface that is lit by the light. When specular light strikes a surface, it reflects in only one direction. This makes the surface appear as if it has a smooth, mirror-like finish.
Warning:
The Open GL settings are cumulative. When all three light component values are set to the maximum, the light source will generate three times the amount of light of a single maximum setting....
Parameters relevant for LightWorks rendering.The LightWorks rendering engine creates views of high quality, but view creation can take time. 
*F
all Off:* Relevant for
Point and
Spot light sources, determines the way in which the light's intensity is attenuated as a function of the distance from the source. By default this parameter is set to "No attenuation", i.e. light intensity is constant. Other available fall-off types include:
*Natural Linear:* 1/(d+1)
*Natural Quadratic:* 1/(d*d+1)
*Linear:* 1/d
*Quadratic:* 1/d*dWhere d = the distance from the light source.
*Scattering:* Creates the effect of light being scattered by a foggy atmosphere.
*Shadow:* Controls shadow display. Increasing
Resolution enables you to smooth the shadow edges. You may get some light and shadow effects by specifying
Quality and
Softness parameters.
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