Gold material. How to setup something for a basic design development evaluation

Up until now, I have not been successful in achieving even a semi convincing look of basic gold material in both Raytace and Bella.
At this timet I’m not attempting final renders inside Rhino because my old and limited hardware makes it very difficult to experiment, do tweaks and adjustments trying to setup from the available default gold.
For final renders I take a winding export path to Keyshot where good results are built in. But that is not practical for making design choices on the go, that has to happen inside Rhino.

I know it is possible, I’ve seen nice results from users here, on both Raytrace and Bella.
But my own efforts got me only as far something that looks like
yellow plastic.

With thanks
Akash

for metals, use black or near black diffuse (base color) and either use a very high ior (>10) or disable fresnel. For yellow gold a reflection color of rgb 255 218 149 is a good starting point. Also add a slight amount of roughness. In rhino 7 with the pbr materials this should all be a lot easier to accomplish.
This what my basic V-Ray gold looks like with ior 35 roughness 10%. The 35 ior is arbitrary, anything above say 20 is a subtle difference:

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Have you tried using the Rhino Metal material, then select a gold color?

Thank you Gijs
Trying with fresnel and IOR 35 [take time on this machine…]
it looks more correct, but very dark.
Seems like the right direction apart from this dark results.

*Similar to Vray, on Keyshot there are no problems to get nice gold. [no access to Vray]
but the thing is, is to be able to have reasonable gold in Raytrace, so it is available during design development without complicated export
[my Keyshot is only available via Zbrush no direct link to Rhino]

It is also a mater of lights/ environment, to get good gold results and I haven’t been very successful here also.

@nathanletwory
thanks you.
This is what I get with the Metal material
it’s a little better but quite far still from a basic gold look that can be useful during design evaluation.

with best regards
Akash

Hi Akash, for Bella, as Nathan suggested, you should use the Metal material and select Gold for the color. Here is a quick example scene for you to play with:

ring.3dm (182.4 KB)

(there is also a new build available (here), which directly exposes Bella materials in Rhino (applicable in this case would be the Metal material, and the Complex IOR material), but it is still in testing stage, so you can try playing with that as well, if you like)

It seems to me this is not working correctly in Rhino, all you can do is crank up the reflection to 100% and disable fresnel.

With rendering gold (Or any other reflective material) your environment is key. With a simple environment it will be difficult to get a convincing look. Furthermore gold will most of the time have tiny scratches that break up the reflections slightly. With Rhino materials there is little you can do about that I’m afraid.

Thank you
I install the new beta version.
and tried to use your example scene but for some reason it crashed rhino, and trying again it was not able to open it…
I can open my other files and I’ll try to new Bella version.
but there’s some issue with the scene file you shared .

thanks a lot
Akash

That’s strange, I installed the current official (20.7.0) version to create the scene, but also checked it with the newer 20.9.0 build. Please be sure to send the crash report to McNeel if it occurs again.

I was just about to ask you regarding this if you have an idea:
I normally do very small details work, and usually manually finish with hand made burnishers [lots of different ones some smaller then a millimetre across the working face]
AFAIU it’s the job of a bump map to create this kind of subtle nonuniform look. But the so called Burnished bump map I could find are all mechanical and uniformed.
I think it is possible scalp a plane with texture like that in Zbrush and a map from that. but it seems like a small project [also making it tile-able]

With thanks
Akash

In some cases it is possible to forgo an actual scratch map and use a material’s anisotropy parameter, if it has one. This biases reflections in a particular direction, instead of reflecting uniformly. Here is a complex IOR gold material with roughness=20 and anisotropy=0:

image

And here is the same material with anisotropy=100% and rotation 45 degrees:

image

I tried again and it open now [after a few minutes trying]
it’s probably because you saved it with Bella display mode as current. and so it loads the models like that [my machine is set to open in maximised perspective ].

it looks very nice.
I’ll try later your scene with a bit more complex object
thanks a lot. seems very promising.

Ah that makes sense, I wish there was a rhino option to prevent realtime render display modes from always starting up immediately.

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I have requested this in the past, maybe more votes will make it happens.

thanks A lot I’ll try to understand the material anisotropy possibilities, but it is quite different then what I’m trying to achieve with the hand burnished look,
here’s an example a photo of an hand made part.
This is an unedited photo so the gold don’t have the exact real look as the physical item, but texture is showing well

I see, yes that’s quite a different thing, and will require various maps. I rendered a skull in this other thread that used gold with some subtle roughness & bump mapping: Sub D challenge 3! … something in that direction, but I was just using some procedural rhino textures, where it looks like your case may need some custom-painted maps.

Here trying to use your setting on another object,
just copied it into your scene without changing anything.
and I can’t get it to render correctly
[gave it the gold material in your scene]

That looks quite different, like the environment has changed. I wonder if copying changed render settings or anything else. If you upload it I can take a look and see.

If you add Rhino Metal, pick correct color, you can then convert to PBR by changing the type to it.

Now you have access to all useful channels like roughness, bump/normal, etc.

Under the hood all basic Rhino materials, with the exception of Plaster, are converted to PBR anyway.

Can I send it to you privately ?
it’s a model I’m currently working on.

Sure thing.

Thank you Nathan
I understand that… but I still am unable to arrive at a usable setting. part of the problem is that try and error adjustments with the available speed of my machine, is very difficult. so the post was about trying to find a good starting place.
waiting to the Denoiser to comes aboard

Akash