Realistic Silver Material in Cycles


(Quantum Anomaly) #1

A happy new year to you all!

I am creating a silver material for jewelry in Cycles and thought it would be worth opening up a thread that would help me in the process and also help others making realistic silver.

To give a clear image here is a collection of reference photos I have gathered from the web.


Observations thus far:
• A silver piece is usually both shiny and dull, depending on the polishing. So it will be necessary to create a UV map to separate the unpolished/oxidized/dark areas from the polished/shiny/bright areas.
• A bump map or two will be needed for the surface scuff marks and bumps.
• There is chromatic aberration present in the photos - is this a property specific to the metal or is it just a result of the camera lens?
• Silver comes in various shades, some warmer, some cooler.
• Silver, although reflective, retains its whitish color.
…This is what I am most struggling with how to replicate now. My silver takes on too much color from the environment, but it needs to be shiny. Any help will be much appreciated.

Please share your ideas on creating silver using Cycles material nodes.


(Quantum Anomaly) #2

Here is an example with environment lighting.
It lacks the white look of silver because it is taking on too much color from the environment.
Got to solve this first…



(moony) #3

Use a different environment light. Any sliver/white coloured material will naturally pick up the colour of the lights/environment. A silver object in a red room lit by red light will appear…red. The majority of the photographs I have been able to find on google images all have neutral grey backgrounds and are lit by white studio flash. A typical flash gun has a colour temperature around the 5000-5500K mark.

If you do a google image search for HDR studio lights - there are plenty that are freely available that have a simple plain backdrop and studio light box/diffuser setups.

Alternatively you could colour correct in compositor. Most of the photographs in your first post will have some sort of colour correction/white balance applied (whether by the camera or by the photographer during post processing).


(Thies Schulz-Holland) #4

I think your silver is too shiny, at least compared to the reference images. Your silver is a near perfect mirror, while the reference silver has a significantly duller, splotchier, almost anisotropic appearance. I agree to moony that the look of silver is highly dependent on the environment lighting - too saturated colors will easily overpower the whitish-silvery look.

Anyway, here’s my try:
This is basically a series connection of paired glossy/diffuse shaders. The first is controlled by a Layer Weight (facing) node to achieve a subtle Fresnel effect. This gets mixed with a hint of anisotropy for good measure. A noise texture creates patches of duller silver on that basic surface, with a scratches image texture to support and “explain” the dullness.

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(Quantum Anomaly) #5

Thank you for the great example!

Ah, yes. Sorry, I should have explained that I was exaggerating the glossiness to demonstrate the problem.
Before when I mixed in more diffuse it didn’t help much.
But now, going with your suggestion of using an anisotropic shader instead if a simple glossy I’m already getting better results.

Yes, those reference photos are mostly if not all shot with studio lighting.
On the other hand I am currently looking at a spoon inside a room that is mostly brown, but the spoon still looks silver colored.
It was my theory that a realistic enough silver material would still look silvery even with various hues of environment lighting.
I could be wrong.
I will experiment more with the info you’ve given me while studying real world examples.
Thanks for the Layer Weight hint too!


(Thies Schulz-Holland) #6

Did have some fun further playing with silver materials tonight…:eyebrowlift2:
This is basically my material setup from the last post, but this time I toned down the scratches and added an occlusion map to create the darker patches in the cavities of the model. I think I overdid it with the anisotropy (and indeed forgot the connect the “Tangent” node for this render) - the material could be glossier and indeed less white.

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(Quantum Anomaly) #7

Wow! That’s really impressive!
Thank you for sharing.
I’ve been playing with the setup you posted earlier.
I need to dig in and study everything about your new node setup. You achieved basically exactly what I was imagining.

How did you create the occlusion map? It’s perfect.
I have been wondering to myself: when I get to that stage how should I do it?
I recently tried to get good ambient occlusion in Cycles and actually got worse results than I used to with Blender Internal.
Clearly I’m missing something there. Gotta go tutorial hunting on that topic.


(Thies Schulz-Holland) #8

Quite frankly: I did it outside of Blender.
I think it’s perfectly possible to bake an ambient occlusion map like this in Blender Internal as described here or here and use that with Cycles, the only problem was that I couldn’t get Blender to UV unwrap this model… It’s a 3D scan, about 600K polygons, all triangles. Any attempt to unwrap that caused Blender to either hang or crash. I therefore had to do the unwrapping in modo - and while I was there, I also baked the occlusion map with modo’s internal renderer. Sorry for cheating, but I still know my way around modo much better than around Blender…:wink:

EDIT
Here’s another attempt, this time “Blender only” (except for the UV unwrap). I combined an ambient occlusion map, baked with Blender Internal at default settings, with a cavity map (video tutorial here). Quite finicky to balance out…

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(Quantum Anomaly) #9

Thanks for the additional info :slight_smile:
I almost asked you before if it was a 3D scan. I kinda figured since it looks hand-sculpted.

Also the more I thought about it the more certain I became that an occlusion map would have to be made using Blender Internal, then brought over to Cycles.

I’m not familiar with modo.

Thanks for the tutorial links as well!
Looking great!


(Didgeboy287) #10

I just found your thread and remembered a post I found from El Brujo recently about finding a tutorial for creating dirty brass. I tried it out myself with some simple settings and got this:



Granted, it doesn’t look as fantastic as the buddah, but the technique may help. Basically, you’re going into vertex paint mode and selecting “Dirty Vertex Colors” under the “paint” menu and then use F6 to play with the highlight angle. According to the tutorial, you’ll be baking an AO map, like you all here have discussed, but hopefully this extra piece will help.


(Thies Schulz-Holland) #11

That helps indeed: It sounds like the technique used in the video I found about creating cavity maps (my last posted link) - but unfortunately that video was without sound and a bit cryptic, so your link fills in the missing pieces. Thanks!

And do you know what’s the best thing about those maps? Just invert them and you get a worn edges shader… Man, I love node recycling! :eyebrowlift2:

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(Thies Schulz-Holland) #12

Hey! Thanks for joining our discussion - and the kind words! The more I have to do with node-based shading, the more I come to the conclusion that nodes are not my way of thinking: I’m a layer guy. I guess that’s what attracted me to modo in the first place - no shader nodes…:wink:

I was not sure how far I am allowed to share the buddha scene, though: The HDRI is commercial, so that’s out anyway and with a different lighting the scenes wouldn’t have been directly comparable. And I had doubts about sharing the model as well (if someone’s interested: it’s one of Jotero’s oldie but goldie 3D scans - rather at the bottom of that page).

So I took the liberty of applying your material to my scene and render that out here - if you don’t mind.
Attached is the render and the final node setup of the buddha “El Brujo style”. I re-used the AO and cavity maps I rendered in BI for my last buddha render. It renders faster than my solution (11:51.58 vs. 14:35.16 in 2000 x 2000) and looks just as well. And it solves a few problems I had with the mapping of my scratches and noise textures on the quirky UV map (which doesn’t matter for baking, but comes back with a vengeance when using other maps).

I might have adjusted the colour of the GGX glossy shader a bit to make it “whiter”, but since the environment is dominated by darkish grey colours I guess that’s ok.

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(elbrujodelatribu) #13

Thanks for making the render and the links @IkariShinji! I agree with you. The material is a bit dark but it might be the background reflection. I could also change the map range parameters, to 0.01 min and 0.04 max. I think the material is too rough, but it depends on the age of it you want to show.


(elbrujodelatribu) #14

Another silver material. I have tried to do it brighter:


I have use the “Dirt Vertex Paint” from the tutorial I posted above. The parameters I used are: Blur Strength 0.5, Blur Iterations 3, Highlight Angle 115º and Dirt Angle 85º. With this parameters I have got a contrasted result. It is as follows:


This information is saved in the Mesh Data. The default name is ‘Col’. I use this information to mix between silver a dirt material. I have used a Color Ramp node to tweak the value. This is the final node setup:



(Quantum Anomaly) #15

Nice quick solution, and probably a good place to start for creating a more detailed occlusion map as well. Thanks for sharing.
Curious about that node setup.

Haha, I love it!
Worn edges maps are the topic of entire threads, and you just came up with a solution for that seemingly as an afterthought.
Nice thinking. Makes perfect sense to invert occlusion to get edge wear.

I took my eyes off this thread for a few days thinking all that was to be said had been said. Glad I checked back!
Ironically I have been busy producing actual metal objects from Blender. But more on that at another time. :slight_smile:


(Quantum Anomaly) #16

Great results! I like that it reflects colors from the environment while still retaining its own white/silver color.
That’s the effect that had been evading me. I shall recreate your node setup and play around further.
Many thanks.

By the way, where does everyone keep getting this Buddha sculpture mesh? lol

Edit:

Oops, I had overlooked this the first time. Great model resource. Thanks!


(Quantum Anomaly) #17

I thought this was on topic - a video tutorial for quickly creating cavity maps:


Once again, thank you Andrew Price.

(SeanPercy42) #18

Well done on this! I am making some silver jewelry graphics for a website I’m working on and your nodes will be extremely helpful. Thanks a million!