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New in Xenon Drop 2
Diffusion is a blur effect, similar to Gaussian blur. In the context of lighting, it is most useful for replicating the effect of seeing lights through a diffusing medium like cloth or tracing paper. This is a standard technique used in photography and film. Learn about the settings for Diffusion below, or take a look at these examples of Diffusion in action.
Example 1 - Diffusing the Sun
Example 2 - Diffusing Bright Lights
Example 3 - Lighting through Tracing Paper
Diffusion Filter Settings
Type - Spherical
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With the Spherical setting, Diffusion blurring is correctly applied taking into account the image is a HDRI map with lat-long mapping. Therefore, the blurring is uniform when the image is mapped onto an environment light, and it is blurred correctly across the left and right edge of the image. The blur also conserves light energy - so as the map is blurred more and more, the amount of light energy it contains remains the same.
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Accuracy
There are 3 accuracy settings: Low, Medium, and High.
The higher the setting, the smoother the result but it will take a little longer to render.
Type - Planar
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Use this setting to apply Diffusion blurring to flat images. For example the appearance of an Area Light.
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