Condensation Technique

[mitchino]

I'm doing a job with condensation on lager cans. I've tried the Greyscale Gorilla droplet Cloner technique, but also want to try using materials. I've got some droplet image maps, for displacement, normal and a mask for opacity, but I can't get things working in Corona. I'm trying to stack materials but the drops are doing weird things. I've also tried a layered material but can't get that to work. What's the best technique?

[davetwo]

can you attach the scene file? Then it would be easier to see where the problem lies. using a displacement map should work if it's set up correctly

[Beanzvision]

Recently I have been doing this using Mograph and a simple sphere with some deformers for shaping. I don't think there's a proper workflow, just what looks/works best for you. ;)

[davetwo]

Actually i think this may be a bug.

I tried a test file with the displacement method using a poliigon shader:

With 2 surfaces - one with the can material and one with the condensation - it sort of works. But if you stack the condensation material on top of the can material on one surface, it turns black.

Adding caustics makes it darker too. Turning refraction value to 1 doesn't help either.

images attached for ref

[PROH]

I don't think that's a bug. I would say it's expected behavior. With only one surface, you'll have a black hole behind every drop, plus the sides of the drops will be metal (as on you picture).

[davetwo]

Hmmm, I suppose that's probable.
I seem to have some distant memory or c4d stacking working OK like this. Maybe I was mistaken.

[houska]

Yes, PROH is right. Stacking works pretty much the same as a layered material would. What you get in the end will always be a single surface with materials combined from the material stack.

[Redeemer]

I'm not sure what the GG droplet cloner thing is (do they have a plugin for that as well?) but I would go for the Mograph option.

Model a few drops, put them in a cloner and use a push apart effector to keep the droplets from intersecting each other. To top things off you could use a shader effector to make the scattering less repetitive.
I used to use forest pack in max to create these droplets, but with the multi instances inside the cloner object option it is not really an issue to scatter 10000 droplets over a surface. Maybe this is a bit more trial and error (i guess that is what cgi is all about) but you'll get a unique condensation on your object instead of a map that has been used many times already.

Good luck!

[Beanzvision]

Anyone with Mograph is welcome to use this test scene. Feel free to edit the crap out of it ;)

[mitchino]

Yes, I'm finding the mograph technique is generally better, however there are a few problems I can't figure out, the main one being that when using the push apart effector (for which you actually have to use scale apart mode, or the drops move away from the surface), means that some of the drops end up so tiny they just look like rendering artefacts rather than drops. I'd like to use scale apart, but restrict the drops size to neither too large or too small. It seems a really hard balance to get right.