Help to make diamond rendering like this file

[Tiouy]

Hi to everyone,
I started with Blender 1 month ago to use for rendering mostly. I’d like to make this diamond shading result but even with the file I don’t manage to the same result. I’d like to simple understand how to make it, it seems it’s with 2 scenes so we see metal through the diamond, I like the idea to get closer to reality and light is hitting these stones…
I found several tutorials for diamonds, but I’m not satisfied so far.
Ideally I need the same reasult for gold and silver metal color.

• Here is the file : https://drive.google.com/file/d/1AGwybJ1meOr7dFl05Nn9ZqFQT7Vs933Z/view?usp=sharing

• Here is the render of this file :

THANKS !!!

[digitvisions]

Hi, no diamond in your file?

[Tiouy]

everything is in the file, you can see them if you select SCENE 2 up there :

[DNorman]

EDIT this answer is not correct, I am leaving it so as not break the discussion) see the next post.

There is something in the Diamonds object properteis that blocks the shader from working.

It looks like the file was setup for Luxcore and there are luxcore custom properteis in the object.

I tried deleting them but it sill did not work, there must be some other left overs that I did not find.

So I added a new cube gave it the same mesh data as the original Diamond and the same material. This worked and it rendered properly (I also had to scale and change rotation of the cube to place it.)

As for the “silver” reflections you need to change the “mounting” colour (behind the Diamond) to silver instead of gold.

I only corrected the large diamond the smaller ones have the same problem.

The file
Gold and Dimond Ring2.blend (752.6 KB)

[Tiouy]

Hi DNorman, thanks for this new version ! It looks nice !!
Actually, the file has been made 8 years ago, here is what was added as informations by the author of this file :

"This is one of the most advanced Blender 3D rings on the market. It uses multiple scenes, layers, and a mask to make the diamonds look as realistic as possible. The diamonds use a special shader to give them rainbow dispersion just like a real diamond. It uses these methods because when the diamonds are in the ring they can not receive enough light for good dispersion. I found a work around that let the light pass through the ring and into the diamond with out effecting the ring. Also the gold ring material is PBR and can be changed to any color. The ring and diamonds are parented to an empty object. This model also has super fast rendering time because you do not have to render the whole image at high samples just because of the diamonds. In this model you can change the amount of samples for the diamonds only making for super fast render times. For example you could render the ring at 200 samples and the diamonds at 1200 samples. *

Features
Advanced render set up to ensure realistic diamonds
Realistic rainbow dispersion
Custom material for diamonds
PBR materials
*Faster render times *

*Note: Due to advanced methods used in this model appending this model to your scene can be quite confusing. Look at documentation and Q&As for a tutorial. Thanks for browsing!"

There is even a video but I don’t really get the point : https://www.youtube.com/watch?v=H6grNXBA60g

[JaAlVir657 (JaAlVir)]

Hello,

Here is what I get, keeping the characteristics of your file :

You need to adjust the Rendering Properties.

Additionally, there are two small modeling errors :

A.- replace the “Ngons” circle with a “Grid Fill”.
B.- adjusts the position of the last “Edges loop” so that it welds correctly to the mirrored part.

Good

[DNorman]

OK now I understand the file (I did not check if there were more scenes).

The diamonds are in one scene (called Diamonds) and the ring in another (called scene) that is why the diamond collection was turned off in the ring scene.

The 2 scenes are then composited together once rendered.

You will not see the result in the viewport (even with viewport compositor because viewport compositor does not allow render passes) you have to render the ring scene (Called Scene - that has the compositor nodes) with the render button for it to work. The final render will give you this result once it is composited

This is your original file, (I did nothing to it- except switch to GPU render and turn on denoise) on the left the viewport on the right the render and compositor result.

Just hit the render button in the main “Scene” and wait for it to render out both scenes and composite them.

The reason they used a separate scene for the diamonds is so the light comes through the back of the diamonds adding nicer reflections (it also means that the diamonds do not reflect the golden mounting.)

[Tiouy]

Absolutely !
So you think this way to make diamond effect is still good for the current version of Blender ?

[Tiouy]

Thank you !!
Very interesting, could you share the Render Properties that your setted up ?
Describe maybe also the process for rendering ?

[DNorman]

Well yes, it still works!
It is a bit of a trick because the diamond is not influenced by the mounting but the result looks great.

With this method the lighting of the diamond is independent from the lighting of the scene, that gives you flexibility to tweak it better without effecting the rest.

Also as they state in the video they use less samples for the ring Scene and more for the diamond scene so it speeds up the result.

[DNorman]

@Tiouy

Very interesting, could you share the Render Properties that your setted up ?

I did not change the settings, the only thing I did was turn on de-noising (only in the diamond scene but you could do in both) and change from CPU to GPU.

[Tiouy]

thanks for your feedback !

[oo_1942 (Kim)]

Please refer to the link below. It shows you how to visualize jewelry using Blender.

https://www.youtube.com/@RohrbachJewelryDesign/videos

[Tiouy]

Thanks I managed to make the rendering as expected, but still need to understand better Blender logical

[DNorman]

Hi Tiouy answering here your PM as others might be interested.

@Tiouy

It’s paining for me as I miss explanations from the different settings.
I’d like to know if you would agree to explain me with a visio and help me to apply it to another model. My need is to get this sparkling effect all the design I modelize.

There is not really an easy way to explain, this as it is a complex setup.

Here is a similar example with a less complex scene and workflow, the theory is the same there are 2 scenes one that renders the ring and room and the other the diamond.

The diamond scene

In the diamond scene there are collections set to holdout and most of their objects have their ray visibility turned off so they do not reflect. The exception is the “grips” that do have reflections turned on in their ray visibility settings so they reflect on the diamonds surface.

The diamond scene is a “full copy” (not linked) of the mount scene, that way you can set the ray visibility of all the objects without effecting the objects in the original scene.

I did not use the “indirect only” option in the compositor instead I set the ray visibility for each object separately.

The diamond scene uses a different world setting and has 2 extra area lights that give you extra reflections in the diamond. I put one of the extra area lights inside the diamond to get even more reflections.

Check the outliner of the diamond scene, in the view layer view note that holdout makes the objects in the collections mask the image. The render properties are set to “film transparent”.

Also you can set the render settings differently in each scene I gave the diamond scene more glossy and transmission bounces. The more glossy bounces the more complex the reflections get.

The mount scene

The scene called mount is the one with the compositor setup that will render both and composite them. I added some streaks on the diamond in the compositor too you might want to get rid of them.

Compositor setup

The idea is that you can add extra lighting and reflections in the diamond scene to get more “sparkle”, decide if the other objects reflect or not and use a different world setting. This method is not realistic.

The result

If you have more doubts you should look up tutorials on working with scenes and using the compositor to mix them, holdout collections and object ray visibility. To make setups like this you need to be comfortable working with different scenes.

I am afraid that there are many settings you can tweak and I can not go through them all.

Here is the file for you to study, this file is less complex and should be more understandable.

d2.blend (246.7 KB)

[Tiouy]

Hey DNorman,

Wow, thank you very very much for you complete answer and easy to understand. Indeed, you really simplyfied the process for what I was expecting…
I spend some hours on trying to duplicate the effect on another object, and I understand that this always should be adjusted according the project. For example, I did a ring with more than 1 stone and I could not put a light inside of each stone, so I applied a HDRI in the world and I am quite satisfied of the result, let me know what you think… For some models I have about 800 diamonds

Here is the file : https://drive.google.com/file/d/1nPHzQAIYSjip-L5lEHIlz5weGd11lE1g/view?usp=sharing

Now I need to get closer to this reality, because beautiful diamond have fire inside and a little bit of ice like this :

But I guess that the effect is different from a photo or a video :

COLLIER DIAMANTS 24 CARATS REINE OR BLANC 18K - 750/1000

[DNorman]

That looks great, I think you have understood the concept.

Yes with this method you will probably want to tweak things differently for each situation.

“Fire”, bare in mind that you can add all sorts of lights and things to the diamond scene to get different reflections, maybe a few small orange/yellow lights would give you a bit of that “fire.”

Looking at the video you could use Bloom instead of streaky sparkles (or a bit of both) either way I would keep it subtle.

You might want to take a look at Drvquiron’s work, he specializes in jewelry.

@Drvquiron

He uses Luxcore due to his love of caustics, in this video he describes his method, towards the end he explains that he uses extra lights to get nice caustics (without using a different scene), which is sort of a similar concept. (Diamond specific lights).

Luxcore Rendering tutorial 3D Jewelry render version 2.6 Blender 3.2

It is a different workflow but you might find it interesting.

[Tiouy]

yes I know his work I will check out Luxcore add-on !
Indeed, the light effect depends of the light, best is the sun for the diamonds but not for the metal (i’ll try sun on diamonds only), then LED spot lights with a warm white are good !

Some fire here

I added some Fresnel to the diamond material to bring more “complications”…
I think know I have to play with the environnement

[DNorman]

Looking good!