control brightness of glass material for Diamond

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dsc16789
Posts: 1
Joined: Tue Jul 16, 2019 12:43 pm

control brightness of glass material for Diamond

Post by dsc16789 »

hi

I have worked over gold ,but diamonds don't look much brighter, how can i increase brightness only for diamonds in my scene .
cant add more lights it brightens whole scene.
The attachment r & d 3.jpg is no longer available
r & d 3.jpg
epilectrolytics
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Re: control brightness of glass material for Diamond

Post by epilectrolytics »

If you want brighter diamonds you should try to darken all other materials in the scene (gold and ground) and then increase overall brightness via tone mapper.
Fox
Posts: 437
Joined: Sat Mar 31, 2018 11:17 am

Re: control brightness of glass material for Diamond

Post by Fox »

I like to use low or medium contrast HDR lighting for gemstones.
https://hdrihaven.com/hdris/category/?c ... &o=popular
wasd
Posts: 319
Joined: Tue Apr 24, 2018 7:20 pm

Re: control brightness of glass material for Diamond

Post by wasd »

diamond-2.jpg
That's what I did:
  • added volumes for world and diamond
  • disabled camera volume
  • switched engine to bidir and sampler to Metropolis
  • set color profile to filmic
  • mixed with denoised image 50/50
  • maybe I forgot something
Diamond is translucent, so it will not be bright unless it's reflecting some light right into the eye or is rough or dirty. I guess everyone wants their diamonds be polished and clean, so it should send rays to the eye.

That one is not denoised (probably)
diamond-4.jpg
different lighting:
diamond-5.jpg
Attachments
rnd 3-wasd-b.zip
(1.9 MiB) Downloaded 118 times
CPU Bidir + Metropolis | Core i5-4570
epilectrolytics
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Re: control brightness of glass material for Diamond

Post by epilectrolytics »

Here's a modified version with darker materials and larger aperture:
rnd4.jpg
rnd 4.blend.zip
(1.97 MiB) Downloaded 139 times
epilectrolytics
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Re: control brightness of glass material for Diamond

Post by epilectrolytics »

When I try to render this with caustics, I see a huge difference between BiDir and Hybrid :?:
bidir.jpg
^ Bidir
v Hybrid
hybrid.jpg
(diamond=only glass node and gold = only metal node)
Last edited by epilectrolytics on Tue Jul 16, 2019 3:26 pm, edited 1 time in total.
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B.Y.O.B.
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Re: control brightness of glass material for Diamond

Post by B.Y.O.B. »

If the diamond is gray, it means that the environment is gray (which is reflected).
Place some large area lights behind the camera so they can reflect in the diamond.

It's probably also important to have an accurately modelled "working" diamond shape (they are optimized to reflect as much light back as possible) and correct IOR (see our IOR node), otherwise total internal reflection might kill some of the highlights.
wasd
Posts: 319
Joined: Tue Apr 24, 2018 7:20 pm

Re: control brightness of glass material for Diamond

Post by wasd »

lighted with hdri
diamond-6.jpg
CPU Bidir + Metropolis | Core i5-4570
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