Autodesk 24000-000000-9860 - Revit Architecture - PC, User Manual

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Issues and Solutions : To solve the problem, try the following:
■ Exposure : Check the exposure setting. Try using a darker exposure. See Adjusting the Exposure of a
Rendered Image on page 1168.
■ Initial Intensity : The Initial Intensity settings for the light sources may be incorrect. In general, Luminous
Flux (lumens) provides more accurate lighting in a rendered image than Wattage. Determine the
manufacturer value for lumens, and enter this value for the Luminous Flux parameter of the Initial
Intensity dialog. (See
Changing the Initial Intensity of a Light Source on page 1133.)
■ Wattage and Efficacy : If you specify a Wattage value on the Initial Intensity dialog, be sure to also specify
a value for Efficacy. (If you change Wattage alone, you may make the light source unintentionally bright.)
Efficacy is the amount of light (luminous flux, measured in lumens) produced by a light source as a ratio
of the amount of energy consumed to produce it (measured in watts).
Examples: For a 100 watt tungsten incandescent (110 V), efficacy is 175. For a 32-watt fluorescent tube
(T8), efficacy is 60.
After changing the Efficacy value, render the image again. Try adjusting the Efficacy value until you
achieve the desired result in the rendered image.
Elements Are Gray in Rendered Image
Symptom : In the rendered image, some of the elements display as gray. They do not display render
appearances as expected.
Issue : This problem occurs when you upgrade a Revit 2008 (or an earlier release) project that uses custom
materials. During the upgrade process, Revit Architecture upgrades all standard materials to use the new
render appearances. However, it cannot upgrade any custom materials.
Solution : Assign render appearances to the custom materials. See Changing the Render Appearance of a
Material on page 465.
Entourage Did Not Render Correctly
Symptom : The 3D view contains entourage (such as cars and people), but it did not render properly.
Issue : This problem occurs when the entourage objects do not have render appearances assigned to them.
Solution : Assign render appearances to the entourage objects. See Specifying a Render Appearance for an
RPC Family on page 1144.
Plants and Trees Are Missing from Rendered Image
Symptom : The 3D view includes plants and trees, but they do not display in the rendered image.
Issue : This problem can occur when you render an image in a project that was created using Revit 2008 (or
an earlier release), and the plants were defined using AccuRender procedures. Revit 2009 no longer supports
AccuRender procedures.
Solution : Edit the plant family properties to specify a render appearance. Then render the image again. See
Specifying a Render Appearance for an RPC Family on page 1144.
1178 | Chapter 17 Rendering