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- 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 tooas well.
- Diffraction: Control diffraction/glare intensity.
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