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mmp / pbrt-v4

Source code to pbrt, the ray tracer described in the forthcoming 4th edition of the "Physically Based Rendering: From Theory to Implementation" book.
https://pbrt.org
Apache License 2.0
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Undesired side effect on Motion Blur... or expected? #461

Closed pbrt4bounty closed 2 minutes ago

pbrt4bounty commented 12 hours ago

I have detected that the rendering result goes from darker to brighter with each step in which the difference in MotionBlur between the open shutter and the closed shutter grows. 0.0 to 0.25 imagen 0.0 to 0.5 imagen 0.0 to 0.75 imagen

@mmp ??

mmp commented 9 hours ago

Yes, that is working as intended: a camera measures energy (power * time), so if the shutter is open longer, it measures more. Adjusting the film "iso" (as in a real camera) can harmonize that.