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[Max] I need help! / [Theory] HDRI Power, Exposure and Noise relations
« on: 2016-11-21, 17:23:46 »
Hi!
As maru says in this thread, i start new topic, and i try to explain my question better and with examples. Sorry for my English and also if this is stupid question, because i'm new for Corona and rendering. I try to found answer with google and freshdesk, but still do not really understand.
In two words my question is:
Did we need to worry somehow about the power of HDRI, if we can compensate possible low lighting from it with making EV in high state?
For understanding it i make simple test scene with not big window, portal in it (properly installed) and HDRI only for lighting.
First shot was made with default 1.0 RGB Level of HDRI Output, 5 Exposure and after 10 passes i have 10.2% of Noise
Second was made with 50 RGB Level of HDRI Output, -0.6 Exposure and after 10 passes i have 10.3% of Noise
Third was made with 0.1 RGB Level of HDRI Output, 8.2 Exposure and after 10 passes i have 9.8% of Noise
I become confused with this results, because as i read in this thread, topic starter have to avoid Noise with increasing power of his HDRI. He decide to try it because previously he just make his exposure with some high value for compensate low lighting from HDRI, but i can't replicate it and as you can see from links above, looks like low power of HDRI do not really affect on the noise amount. Or maybe i need to learn something else? As i said, i no have before experience with renders and before of asking this question i try to learn anything about the noise in Corona.
Just in the case, sample scene from screenshots (scene was made in max2017 Student Version and Corona 1.5 hotfix2). I never before shared scenes from max, so let me know if i shared it somehow wrong :/
As maru says in this thread, i start new topic, and i try to explain my question better and with examples. Sorry for my English and also if this is stupid question, because i'm new for Corona and rendering. I try to found answer with google and freshdesk, but still do not really understand.
In two words my question is:
Did we need to worry somehow about the power of HDRI, if we can compensate possible low lighting from it with making EV in high state?
For understanding it i make simple test scene with not big window, portal in it (properly installed) and HDRI only for lighting.
First shot was made with default 1.0 RGB Level of HDRI Output, 5 Exposure and after 10 passes i have 10.2% of Noise
Second was made with 50 RGB Level of HDRI Output, -0.6 Exposure and after 10 passes i have 10.3% of Noise
Third was made with 0.1 RGB Level of HDRI Output, 8.2 Exposure and after 10 passes i have 9.8% of Noise
I become confused with this results, because as i read in this thread, topic starter have to avoid Noise with increasing power of his HDRI. He decide to try it because previously he just make his exposure with some high value for compensate low lighting from HDRI, but i can't replicate it and as you can see from links above, looks like low power of HDRI do not really affect on the noise amount. Or maybe i need to learn something else? As i said, i no have before experience with renders and before of asking this question i try to learn anything about the noise in Corona.
Just in the case, sample scene from screenshots (scene was made in max2017 Student Version and Corona 1.5 hotfix2). I never before shared scenes from max, so let me know if i shared it somehow wrong :/