2010

Table Of Contents
area of illumination. (If you have previously completed the Global Illumination
tutorial, you may notice similarities in this area.)
In the next steps, you return to the Render Settings window and the Attribute
editor to increase the quality attributes that affect the caustics effect.
To increase the caustics quality settings
1 In the Render Settings window, open the Caustics and Global Illumination
attributes and change the following Caustics attributes to:
Accuracy: 900
Radius: 1.5
The Accuracy determines how many photons will be evaluated to
determine the Caustic intensity at a given sampling point. Radius
determines the size of the region surrounding the particular sampling
point. The more photons that get sampled, the more realistic the caustic
effect appears in the final image.
2 Close the Render Settings window.
Increasing the number of caustic photons that get emitted into the scene also
increases the quality of the caustic effect. When you increase the number of
caustic photons you increase the density of the resulting photon map that
gets produced at the beginning of the render process. The more photons, the
smoother the resulting caustics effect.
NOTE As you increase the caustic quality and photon settings so will the render
time. Your goal should be to increase these settings just enough to achieve the
desired image quality, without increasing them beyond what is required so that
your rendering times are not adversely affected. Performing test renderings is the
best method to determine these settings.
To increase the number of caustic photons
1 In the Hypershade window, double-click the icon for spotLightShape1.
Render the scene using caustics | 531