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okokoo
02-24-2013, 07:27 PM
Hello all.

So, I'm trying to render some plastic furniture. The problem is that I cant get it to look realistic.
I've tried to use plain emissive material with the result that the surface look dead (same bright colour on all of the part, resulting in That you cant see corners. Next thing I tried was to make a physical lightbulb inside the model and put on a semitransparent texture. Got a slightly better result but had some problems with the model getting to much shadows.

Do anyone have some good suggestions how to make emissive parts (materials)without losing the shape of the model.
Visit www.slidedesign.it to get some understanding how I want it to look like.
Exampels of models is "cubo", "snake" and "ypsilon". Sorry for my bad english.

Best regards,

Ulf

andy
02-25-2013, 11:39 AM
So you'll never really get what you want out of one render pass for that. Render cameras don't work the same way real cameras do.
If you use a transparent material you can come close by modeling everything physical and copying that exactly. Your render time will be through the roof though.

I recommend rendering it glossy white. Make sure nothing is blown out. You can always make it just a Little darker than you need then push it to white in photoshop (recommended).
Render out a GI pass or ambient occlusion pass. This will go on top of all your layers using multiply. You can paint a layer mask to add to areas where you would be putting light bulbs behind the surfaces in order to add a little bit of realism.

And lastly render out something that will give you a good object selection. I recommend an object pass. In photoshop fill with white (or the color of your light) switch mode to add, and blur the layer a bit so it's not too sharp. That will add just a touch of camera effect. If there's something blocking that object, make sure that area ends up looking sharp or it will look like you're glowing in Front of that object, which isn't right.
This one will need to be taken pretty far down in transparency or it will be flat and overbright.

When working with lit plastics you have to fake what the camera would normally see as well as what you perceive when you see an object like that. Especially for white, it's hard to get shape, but still make it seem like it's lit.
If it's in an environment you can also make an object seem brighter by just changing the exposure of everything around it.

Anyway, you'll be looking at passes. Even if you are a photographer, you'd probably end up taking a few shots ,and compositing them together, of the product to get the shot. I use to do interior shots of fridges and always had troubles rendering the interior bright enough in one pass. Then I learned our photographers took 2 pictures to get those shots Every time.

That's probably not the quick answer you were looking for, but I think it will help. If you don't do adjustment layers in photoshop, learn them. It's pretty easy. But they are Extremely valuable. I rarely make a file without using at least 1.

okokoo
02-25-2013, 01:44 PM
Thanks alot for the answer(s) Andy. Was hoping for some magical material but I understand the problem ;-). It's mainly when I use groups of the furniture that it feels unrealistic. If its just one or two parts the result is acceptable. I'm gonna try all the good advices you wrote. Hopefully I end up super satisfied.

Thanks again.

blitz
02-25-2013, 03:00 PM
It's possible to do with a generic material with internal roughness, diffusion and transluscency - make sure to set this material as "solid" and apply to your furniture. Place an emmisive flat model wherever the furniture touches the ground. Make sure the emmissive model and bottom surface of the furniture model are coplanar.

417

It renders and clears up very fast on this cube. Not sure how quickly it will clear up on a complicated model.

You can see the light dispersed onto a non-reflective physical plane too..

418

david.randle
02-25-2013, 05:17 PM
I would have recommended what blitz said....If you have the wall thickness modeled, then you should get a very realistic result. Also, if you have pro, you may want to try a Point Light inside your model or a sphere with an emissive added to it to get an even lighting all around instead of just coming up from the bottom. That depends entirely on the look you are going for though.

thanks blitz and best of luck okokoo

okokoo
02-25-2013, 09:06 PM
Wow! That looks great. That was the result that I searched for. Big ups!!

Thanks blitz and david!

blitz
02-26-2013, 06:01 AM
David has a good point. If you model exactly as per manufacturing, you should be able to mimic the emmission physically by placing bright emmissives behind or under a shell model (model with a physical thickness).

If you need help, PM me. It's all about creating appropriate material attributes to get the results you need. I believe it can all be done without the need of photoshop.

okokoo
02-26-2013, 11:21 AM
Update. Did some new models with the actual wall thickness, got a fine result. There is always some tweaking to do but the result was over my expectations.
I'm happy there are so helpful people here.

david.randle
02-26-2013, 06:29 PM
If you can, you should upload and share the materials in the Community!