Every time I see a webinar I run off to try the techniques I've seen used ... I also start thinking too much. I think "What if ... " and "How do I do ...?"
Here is my latest thought. Silly me only recently discovered that you can ADD shader settings to your objects without replacing what is already there. I've been playing with that as well ... and was wondering how to layer or add effects to shaders already in place.
For example. I have a brick wall. Pristine. Not very realistic, but it's a procedural setting from either a legacy Poser mat file or a Superfly tile/brick. Soooo. How do I add dirt and grime on the wall without losing the integrity of the original brick? Even more so ... how do I make the dirt and grim accumulate as it settles at the base of the wall? This can go for dirty glass, mud ... and other similar effects. Who's up for the challenge? I know this could be done in Lightwave 15 years ago ... so we should be able to figure this out for our beloved Poser.
I think with layers you need to keep in mind that the layers on top of the base need to have some sort of transparency or you will just be looking at the topmost layer.
You can also do multiple mats on one layer with a blend node/ mix closure that is driven by a mask image.
You need to create a mask on those layers to tell where the dirt will go. This is an old firefly render with a mask making a scull cap.
Hmmm. The things I was trying to do ... just kept washing out the lower layers. I'm starting a new thread on an alternative of what I'm thinking of ... Masks.