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2. Bounces
Reflection
Determines how many levels of reflections are permitted. In other words, how many times a ray will reflect off objects. The raytrace recursion process traces multiple reflections. A setting of 0 disables reflections. Higher values cause longer rendering times.
Transparency
Determines how many levels of transparency are permitted. In other words, how many transparent objects a ray will pass through. A transparency setting of 4 lets you see through four transparent objects. Higher values cause longer rendering times