Need some advanced material tips for brass

[stayinwonderland]

Here's my zbrush sculpture with its nice zbrush material:

 

 

and here's my model in 3dsmax/vray:

 

 

and another real life example of brass:

 

 

The main issue is that you can see definition in the creases for the zbrush render and the photo, but it all gets lost in my material.

[Scott Schroeder]

I'd run a tight AO pass or use the Vray Dirt map as a mask to darken up your grooves so you get the dirt effect you see in real life. Right now, your material is perfect brass that has just been cast, there is no dirt no patina or anything.

[stayinwonderland]

I think i might need something more powerful than that. I already have AO turned on, and a dirt map, and a bump map. Need something that recognises grooves or something. Don't even know if that's possible though?

[matthewspencer]

Couldn't it be that your bump is muddying the look of your grooves? Tune the map's severity down and see if that works...

 

Your dirt map seems way too subtle, I can't see any trace of it really. Maybe your spotlight is too harsh?

 

What does a pure-AO pass look like?

[stayinwonderland]

1. I can never really see dirt maps anyway, I never use them for this reason, they're always practically invisible.

 

2. I don't know how to do an a/o pass as there's no render element for that in vray. Any tips?

 

I have found something in zbrush called Cavity Maps. You can mask off the crevices in your sculpt and export that as black with controls over how sharp or blurry it is, then use that as a texture. I'm going to look into that but it may take a few days to learn as zbrush pipeline is astronomically difficult.

[matthewspencer]

VRay "AO pass"

 

You could also forget about noise and crevice maps and just paint a plain old diffuse map using texture painting in zBrush. Some sort of soft and irregular black ink. Then just add it as another material layer. You could further refine the map by alpha clipping it.

[stayinwonderland]

Well, the cavity map does the same thing, just paints black into the cavities. But at this stage I don't have a clue about the pipeline going from zbrush to 3ds max. How to UV, whether to export low subdivs or high subdivs etc. so will have to study that. I don't have it UV'd as of yet and UVs are just a little unfamiliar to me (grey area i've avoided for many years).

 

Thanks for the link, will check it out.

[Corey Beaulieu]

Try using your bump map as a mix map for different diffuse colors and then for variation in the reflection and the glossiness. You can use the bump to mix in a second mix map where you add the original color with with a patina map. To get this right is going to me a pretty deep material. Nothing basic is going to do your trick out right.

 

as to the A/O pass in Vray, it is called vrayextratex element. This takes a map and prints the element link an override. Just put a dirt map into the map slot before rendering. I would do this exclusively and untick A/O to save your render time.

[Chris MacDonald]

I'd definitely render out an AO pass for it (pretty sure you can do that in ZBrush?) and I'd use that as a mask for a mix map between two materials... One a shiny brass, the other a dull brown/grey. Without a doubt the way to go for something like this.

[stayinwonderland]

Ok guys. I've got a few things to be mulling over for a bit and I'll get back to you.

 

Here's another zbrush render just to further illustrate the direction I'm trying to take. Added some noise to the model.

 

 

So I'm going to learn how to export all the fine details from zbrush and see how that renders and see if I can combine the above techniques.

 

Might need to get back to you on some of the finer points on vray materials though.

 

Cheers.

[Scott Schroeder]

You really also should look into UV'ing that thing so you can easily map your high detail from Zbrush onto your medium to low detail in 3ds Max. So you don't have to deal with a heavy sub-d Zbrush model in Max. The real power comes from being able to paint that detail on a map rather than trying to do it all in a material or a render.

[stayinwonderland]

yeah Scott, currently researching that. Much to learn and, while there are a ton of videos, hardly any (pretty much none) resource for quick and clear Q & A with other zbrush users.

[matthewspencer]

zBrush is a nightmare, there's no way around it.

 

If only it wasn't so damn useful...

 

But yeah getting the hang of UV editing within zBrush is key; you'll be glad you researched it.

[stayinwonderland]

Here's my latest render after about 12 hours of study:

 

 

Still trying to figure out how to export from zbrush to vray/3ds max. That in itself is a 48 hours intensive study. Do you know how many different ways there are to export a displacement map from zbrush!?

 

Two of those hours were me, sitting in front of vray RT, tweaking that brass, only to make it worse and worse until reverting back the original and then I came across the vray car paint material.

 

Tried the ambient occlusion pass and it can be 'seen' in the above render. I say seen because it just doesn't make much of a difference apart from to slightly darken a few corners. What I need is a decent cavity map but they just don't work and come out totally EFFED up. Follow a tutorial note for note and bammo, crazy result. Onward.

[John Dollus]

Yes, your max/vray render looks somewhat diluted from the zbrush render.

[Ismael]

Google search "Bronze Old Vray-materials.de"

 

The first two is what I used on these.

 

Edited February 2, 2013 by Ismael
Add image

[stayinwonderland]

Thanks for the tip Ismael! I don't usually like their materials but 1 out of 3 I downloaded worked well (when I combined it with my original brass). here's the latest. What do we think?

 

 

The other components to the knocker will be detailed, for now I'm just figuring out modelling/sculpting and texturing.

[Ismael]

This is a highly presentable brass.