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But the juice absorption is orders of magnitude 100 times stronger. How can you see transmission color if environment reflects light 10 to 50 times stronger. Disney specularity set to 0.01 and roughness to 0.4 and diffuse to 0.2, even so the specular reflection is dominating.

Interesting, is this just bias, or there are indeed more SDS paths inside scattering volume
What a huge time gap between 10 min and 9 hour render. The smaller radius has no scattering volume effects, but renders so long. -------------
EDIT

Nevermind, i got the volume scattering effect to work with small start radius too, using lower scattering asymmetry.

Dade wrote: ↑Tue Aug 20, 2019 7:36 am

FarbigeWelt wrote: ↑Tue Aug 20, 2019 6:58 am It is Not the Glass Container, it is the Glass Itself

You need to have half of the juice directly visible to notice the difference (like in the original test scene). In your test, all the juice is under glass shadow.

Revised Material Test
Sun shines directly top down. There is no sky to get neutral colors. Room‘s walls are very dark (0.02,0.02,0.02) to limit indirect light. Room‘s ceiling has an opacity of 0.02 to let sun light in the room.
Cube rows are shifted to avoid shadowing. Different materials are ambiguous now, e.g. pure Glass is without scattering, Juice Glass is with scattering, Null Absorption is without scattering.
Very interesting is Matte Transluscent because it reflects yellow (red+green) and transmits blue (transmission is white, means clear). Null Scattering (yellow) behaves similarly but unfortunately not as nicely as Matte Transluscent.
Based on this materials study I suggest for Orange Juice to define a Mix material of 60% to 70% Glass (transmission yellow, homogeneous volume with absorption light yellow and scattering white with scale 0.5 to 0.95) and 30% to 40% Matte Transluscent (reflection and transmission white): Engine Path with light tracking and PGIC indirect cache (look up radius not less than 1/10 the size of smallest juice object). Engine BiDir, Metropolis (max. con. rejects at least 4096) requires Glass with Heterogeneous Volume (step size 1 to 10 mm, at least 256 iterations).

It feels little too yellow and OIDN went very bright, so i post raw image. Absorption has to go down.

Caustics shouldn't be yellow?

Asticles wrote: ↑Thu Aug 22, 2019 2:04 pm Caustics shouldn't be yellow?

They are in the darker areas, but not from top edge. Can it be the bright light is clamped or overexposed with linear tonemapper, because sun brightness in exr file is 10 000 000 000 or inf (the original hdr usually has floats under 200k).

With gamma 1 it's 10 000 000 000, but with gamma 0.8 it's around 16 000.

Fox wrote: ↑Thu Aug 22, 2019 2:28 pm

Asticles wrote: ↑Thu Aug 22, 2019 2:04 pm Caustics shouldn't be yellow?

They are in the darker areas,

Where do you see caustics beside the ones from the clear glass body? Without dispersion these are hopefully bright white.

FarbigeWelt wrote: ↑Thu Aug 22, 2019 3:23 pm Where do you see caustics beside the ones from the clear glass body? Without dispersion these are hopefully bright white.

There is mostly noise of it
I see what if i up the absorption and scattering 10 times, maybe the white will be yellow.

lacilaci wrote: ↑Fri Aug 16, 2019 4:04 am

kintuX wrote: ↑Thu Aug 15, 2019 11:33 pm

lacilaci wrote: ↑Thu Aug 15, 2019 4:06 pm I'm not happy and I know that it works differently in other renderers so the question is if it can be fixed. For that I guess I have to wait until Dade comes back home.

Please, then show some comparisons to "juice" you've done with other engines.
I'm interested to see facts about how much they differ from your experience.

I started this thread with comparison to what I get in cycles.

Yeah, that Cycles example ... tried it many moons ago and it didn't taste any good
Overall, I prefer Corona's effortless speed & simplicity.
But now I also have LuxCore preset at hand... so all is good & getting better

Fox wrote: ↑Thu Aug 22, 2019 3:33 pm

FarbigeWelt wrote: ↑Thu Aug 22, 2019 3:23 pm Where do you see caustics beside the ones from the clear glass body? Without dispersion these are hopefully bright white.

There is mostly noise of it
I see what if i up the absorption and scattering 10 times, maybe the white will be yellow.

If you increase scattering less light passes the volume and volume caustics disappear completely.