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- Aperture Map: The shape of the diaphragm will model the pattern of light that reaches the film. For example, a circular diaphragm will create circular patterns; a hexagonal diaphragm will create 6 light streaks. You can set the diaphragm shape using a black & white or color map called the aperture map.
- Obstacle Map: Water drops, eyelashes or dirt on the camera lens will also cause diffraction effects. A black & white map called the obstacle map is needed. If you do not want to use an obstacle map, you can leave this path blank: you only need an aperture map for diffraction to work. However, if you do want to use an obstacle map, be aware that it is necessary to load an aperture map too.
- Diffraction: Control diffraction/glare intensity.
- Frequency: Control the frequency of coloring in the diffraction effect. Higher values will make the patterns denser.
The obstacle aperture map and the aperture obstacle map must have the same resolution. Your render and the maps used do not always need to have the same resolution, but the more similar they are in resolution, the less diffraction distortion you will get. The aperture map should be black with white specifying the shape and size of the aperture. The obstacle map should be white with black areas specifying dirt or scratches on the lens surface.
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