Dirt on a potato

[stevesideas]

Hi guys,

Ive modeled a potato and want to put mud/dirt on it. I need the dirty areas to look photoreal...the type of dirt that would remain on the spud after you have washed it. Basically its built up areas of mud. I thought displacement would work, but it just looks wrong...cant seem to work out a good way to do it.

Any ideas ?

[joconnell]

mix between two different materials with a painted map or a noise map of some kind - use the same map to control your displacement settings. The dirt depends if it's supposed to be big clumps or not? Either way it'll be two totally different material settings in terms of your glossiness so it'll be a bit easier to tweak with mixed bits. Very soft, broad highlights on the dirt and something waxier on the spud. You got any test renders so far?

[stevesideas]

Yeah, heres a test render. I have the potato looking good enough, this dirt is looking crap at the moment. Ive basically put another potato exactly the same shape inside the outer skin version and then applied vray displacement to bring up the bumps of dirt.

[joconnell]

Getcha - I'd probably make a far softer transition between the two and use a lower displacement amount - the lighting doesn't seem to be too flattering on it either. I'd say you could get it in the one object and use your blend maps to control the areas that are dirt / displace and not. The crisp edges that are there at the minute make it look like a cracked outer shell of dirt - they don't seem to tie on to it that nicely - it's as if the spud had a full casing of dirt around it and it's been chipped off - maybe blend the edges so the graduation into the displacement is a bit softer?

[roppin]

Or I´d make the dirt in the same texture as the potato skin. and separete glossy etc. with bump and reflection maps. if it looks like a flat dirty potato, it will probably look good rendered.
/Daniel

[stevesideas]

I tried a number of solutions but just couldnt get the texture and model right in the end. The client has agreed to forget the mud...it was an addition I proposed in the first place. It did look good when it was a small render but these renders need to be 300dpi at A4 and it just didnt look good when it was rendered out that large.

[stevesideas]

Thanks for the tips though guys

[roppin]

I guess I´d use alot of PS if it´s for a still. I hate prints, will never go back there... I love standard definition; you can get away murder...

[stevesideas]

I think its quite challenging doing the larger versions and Im sure with enough time I could have cracked it, but with a tight deadline a choice has to be made.

[tricky]

Is it me, or is this just a bonkers thread: 'Dirt on a Potato'. I love the variety of work on here.

[stevesideas]

Yeah. Its one of the most peculiar jobs I have done. The client even commented on how odd the conversation was about this project. Good to do varied work though.

Edit: The above comment would make more sense if I added that Im making potatoes in the shape of famous people..heh

[Da_elf]

so is the dirt symbolic of the dirty scandals that usually hover around famous people? hehehe

[stevesideas]

It could be...

This project is actually a nightmare...out of everything ive done in the last 4 years this is the hardest...trying to make a potato look natural (as if it has grown into this shape) and yet look instantly recognisable like a famous character...i personally think its a contradiction of directions.

[Neilg]

I'd just model the famous people and get them made into a metal mould.

Find a small potato that's still growing, clamp the mould around it and you'll be sorted after a month or so.