how to achieve dark edges with vray dirt?

[lukx]

I'm not sure what I'm doing worng but I somehow can't get dark edges when using vraydirt.
Here's sample scene: https://www.dropbox.com/sh/iqndvrxew6i1n67/gXXtqZ3GiY . I made very dark texture for occluded color but it doesn't seem to have any effect. I even used vraycomptex to multiply effect but still nothing.

[Pixelcon]

Your material is working, it's just very subtle. The guy over at viscorbel has a method of stacking his vraydirt within more vraydirt maps to multiply the effect. It's tricky to explain but take a look at the screen shot i've attached. basically you stack the vraydirts within the unoccluded slot. You need to copy the settings for each one, and I would hazard a guess you need to copy the maps too but it might require a bit of testing.

[vlado]

You can also use an Output map to remap the output of V-Ray dirt and increase its contrast as needed.

Best regards,
Vlado

[Pixelcon]

^ sounds about a million times easier....

[Morbid Angel]

Hey Lukx check this file. I named all the nodes there for pretty much self explanatory and also mixed a few procedural textures to better show the effect. I think one of the issues you have is that your "dirty" texture is not dark enough, also your vray comp texture is actually set to add, not multiply. Lastly I think using a texture inside the radius with a very low value will create a radius so short it will not be visible. I had pushed the value around in my setup primarily you want to pay attention to distribution which bends the normals around to create more of AO effect.

Remember to clamp your maps if you end up pushing their values around it can create overbrights in your scene. Vray already clamps them in diffuse though.

https://www.dropbox.com/s/wozc3eaon9xmuoc/dirt_dv.zip

[Jiri.Matys]

Output map is good, but if you wanna great results with exact look, you have to use multiple vraydirt linked to unoccluded slot as Pixelcon said, its really great. But use minimum of 16 subdivs, with 8 it didnt work.