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In this image you can see all of the larger water drops (a couple are pointed out in red) are showing up much darker than the smaller ones. It seems they are getting no caustics or something?
Water drops are created using displacement map and alpha. (don't just the map, this is just a placeholder for test). Lighting is just an HDRI environment

I'm using PMC with a spec depth of 8 and Diffuse of 4. Raising those values doesn't change anything. This image is at 500 samples but the one I did last night before it crashed was up to 1000 samples and there was no difference whatsoever. I know for small images that would be a low sample amount but something this large, it should be plenty enough for those to clear up.

Any clue why only the larger drops are dark and the smaller ones are fine??

Just a guess - have you got alpha shadows enabled?

hi,
have you tried to play with the rey epsilon value?
ciao beppe

Got it figured out, I didn't have "Fake Shadows" turned on in my materials. Overall, i think these look passable but i'm not real convinced about what's going on in the bright highlight on the front (drops are still dark) and the drops on the left side looking like bubble wrap, although that could be an issue of the lighting, I dunno.

With fake shadows enabled you won't get accurate caustics in those drops, that may affect the look of those drops.

I think the things you need to check are the maximum depth, the ray-epsilon value and the caustic blur settings in the kernel node. What are the material settings for that tin can?

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Roeland

Here are my render settings. pretty much just the default settings in PMC. Anything look off ? Can material is just a basic glossy material. Water drops are displacement with alpha.

This has always been something that's bugged me about the "Fake Shadows", or rather Specular materials in general. If Fake Shadows is disabled, then you should get accurate caustics, even if it takes slower. But in my experience it is always darker, which is incorrect.

As a workaround I suggest turning fake shadows off and turning up caustic blur to about 0.05, that should help. Mess with that setting as necessary.

profbetis wrote:This has always been something that's bugged me about the "Fake Shadows", or rather Specular materials in general. If Fake Shadows is disabled, then you should get accurate caustics, even if it takes slower. But in my experience it is always darker, which is incorrect.

As a workaround I suggest turning fake shadows off and turning up caustic blur to about 0.05, that should help. Mess with that setting as necessary.

Thanks, I'll give it a try. And yeah, i've never quite understood why having fake shadows turned off seems to break the specular material in some instances...such as this. Hopefully your settings suggestion will help!

How did you make such nice condensation ;D ?

I'm also interested in how you made such nice condensation. Looks great!