Hi,
Please check this render for comparision. Originally i rendered this with Arnold and I tried to get same results in Cycles but it lost much of detail in Cycles, then I rendered it with Vray and it looks better than Cycles, closer to Arnold. Both Vray and Arnold give nice shadows under the cheeks and on the temple. In Cycles I lose this detail. Already tried to turn off caustics and clamp indirect samples in Cycles, it gave me darker shadows - closer to Arnold/Vray but still those nice shadows on the temple are missing. Can you give me some tips how to make it looks closer to Arnold/Vray? Is it possible to adjust how much light “spread” from area light? You can do it in Maya/Arnold.
Looks to me like just a more aggressive fresnel in the other two. Adjust your material? Or maybe it’s down to GGX/Multiscatter GGX.
What do you mean by more aggressive fresnel, higher IOR?
In Maya/Arnold I could adjust BRDF between Oren-Nayar and Lambert and I think this would help here, there is something about different BRDF types in Blender here https://docs.blender.org/manual/en/latest/render/blender_render/materials/properties/diffuse_shaders.html
but i can’t find where to change it in Blender
Have you used the Principled BSDF shader or a combined/mixed shader?
Without knowing the material setups for all renderers, no one could give a safe answer.
Principled BSDF shader
white color 80%
nothing else but specular 0,5 (equal of fresnel IOR 1,5) and roughness .390
no other changes
Those are just diffuse BRDFs. I wouldn’t expect much difference there. You obviously have some kind of glossy term here, so that’s where I’d look. Either IOR or BRDF difference.
And yeah, we don’t know your shader setups, so we can’t really point you at anything concrete.
From what you said, it doesn’t seem you’re using the Principled BRDF, so try that. It’s somewhat more correct than a Diffuse/Glossy mix due to the per-microfacet fresnel term.
Conversely, if you’re not using the disney shader on the other two, then that may be it as well.
That might be it. Afaik, Arnold does not support Multiscatter GGX, but uses GGX instead. Cycles has enabled it by default. Maybe try changing the Principled BSDF to GGX to get a closer result to Arnold.
Another Possibility is a different LUT setup (filmic)
there is nothing fancy, just 4 lights, a sculpt and very simple Principled BSDF materials
I can’t find any other BRDF types (blinn, phong etc) only GGX in Principled, I tried changing Multiscatter GGX to GGX too
Yup, your arnold and vray setups seem to be behaving as though they’re just doing the fresnel term averaged instead of per microfacet. This is less physically correct than Blender, but meh, who cares.
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thank you 
I don’t know Blender yet, so it’s a mix of non PBR materials… but for me it looks better, thanks again
one more question, do you know where can I find those shading types that official doc says abou? It says about Lambert, Oren-Nayar etc. I can’t find anything like this in Blender. Is this doc obsolete?
https://docs.blender.org/manual/en/latest/render/blender_render/materials/properties/diffuse_shaders.html
Um, well, you were looking at shaders for the old Blender Render engine, not Cycles.
However, nobody actually wrote anything about the shaders in the docs for Cycles 
https://docs.blender.org/manual/en/latest/render/cycles/materials/surface.html
It’s kinda ridiculous. I only know what I know because I’ve been following the commit logs for years, but new users can’t really be expected to catch up on that. Sorry. 
Your best bet is using the search function on these forums a lot, I guess. And ask questions, people will answer.
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Ok, thanks again
If you want information on the Principled BSDF specifically, your best source of info is this paper:
But that still doesn’t tell you all the details of how it’s implemented in Blender.
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The docs for the shader nodes are here:
https://docs.blender.org/manual/en/dev/render/cycles/nodes/types/shaders/index.html
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Oh wow. Seems I’ve been blind 
it almost works now, but I had to give roughness ,140 instead of ,390
if i go for ,390 i lose all specular it looks like non reflective material 
Yeah, the roughness in Cycles is non-squared (it was implemented before that was a thing), so the number equivalent to your arnold and vray setups would be 0.152.
If you use roughness textures later, you should square those too with a math node.
Not sure if this is getting brought in line in Blender 2.8 or not.
but I saw on your screenshot that u had roughness ,390
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Yes, I forgot.