Infinite reflection mirror (physically accurate)

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Noah_
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Infinite reflection mirror (physically accurate)

Post by Noah_ »

Little else, what the title says

What would be the number of rebounds for this in general?

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Full Hybrid Back/Forward path tracing - I don't like clamping - Bidir it's great but very slow - I have 4096 MiB de Vram and I want to cry.
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B.Y.O.B.
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Re: Infinite reflection mirror (physically accurate)

Post by B.Y.O.B. »

It depends on the reflectivity of the mirror, just do some tests with higher/lower path depths.
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Noah_
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Re: Infinite reflection mirror (physically accurate)

Post by Noah_ »

B.Y.O.B. wrote: Thu Feb 27, 2020 10:56 am It depends on the reflectivity of the mirror, just do some tests with higher/lower path depths.
the mirror seems not to meet the mirror criteria

or I am doing something wrong

https://physics.stackexchange.com/quest ... y-infinite

Mirror
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Metal with Roughness 0.0010
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Metal with Roughness 0 (Constant Value 0)
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Full Hybrid Back/Forward path tracing - I don't like clamping - Bidir it's great but very slow - I have 4096 MiB de Vram and I want to cry.
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Noah_
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Re: Infinite reflection mirror (physically accurate)

Post by Noah_ »

oh... never mind

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Full Hybrid Back/Forward path tracing - I don't like clamping - Bidir it's great but very slow - I have 4096 MiB de Vram and I want to cry.
CodeHD
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Re: Infinite reflection mirror (physically accurate)

Post by CodeHD »

I can't open any of the images you linked, so I have no idea what exactly you are trying, but just to give you an extra hint to what the stack-article already says:

Typical household mirrors are so-called second-surface mirrors, i.e. a reflective silver layer is behind a sheet of glass. So you will have losses from the reflection, which is not 100%, and absorption from the glass. As a note on the reflectance, I have often seen them to leak some light through the backside paint, as the silver layer is not quite thick enough. So a realistic assumption would be 90% reflectance, perhaps even lower. In comparison, standard laboratory first-surface silver mirrros are around 96% for visible light.

This old thread might also interest you, as it contains anotehr real example:

viewtopic.php?f=2&t=917

Edit: Now, after writing the answer, suddenly the images display... The luxcore mirror material is just simply an ideal mirror, i.e. 100% reflective. Not sure how metal is defined internally. You can always try mixing mirror with perfect matte black, if you want to play around with tuning reflectivity.
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Re: Infinite reflection mirror (physically accurate)

Post by B.Y.O.B. »

CodeHD wrote: Thu Feb 27, 2020 5:43 pm The luxcore mirror material is just simply an ideal mirror, i.e. 100% reflective. Not sure how metal is defined internally. You can always try mixing mirror with perfect matte black, if you want to play around with tuning reflectivity.
Changing the reflection color of the mirror material should be enough.
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Re: Infinite reflection mirror (physically accurate)

Post by CodeHD »

Right... I forgot about that :oops:
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