light and material study

[JeZ]

Hi guys,
This is my first post here. I am an happy new owner of a twilight license

My first goal is to understand how to setup materials to look as realistic as possible and find a way to easily light a "studio" scene which I have difficulty with.

Material part:

I am mostly working with wood, glass, opaque lacquers and metal. Right now I am focusing on wood materials. I have been trying to figure out how to use arroway textures for a while with more or less success.

lighting/studio:

I tried a couple of studio components and built my own. I tried hdri studio skies without success, then tried spot and point lights. Nothing wow. I need to work more on that.


Heres a first material study. What I did is:

The wood material is an Arroway sample. I changed the color in the sketchup edit menu (dont know if it is a bad idea). template satin plastic. I put the reflectivity map and the bump map (size .6)

The glass material is flint template with a blue greenish color.

That scene is lit by 2 point lights.


I would deeply appreciate any hints, C & C.

Thanks.

Jerome

[Fletch]

Hi JeZ, bienvenue,

For wood, I use Plastic template most of the time... I find myself cranking up shininess sometimes to 600, 1000, 1500, even 5000 depending on the situation. The Plastic "Shiny" template defaults to 180. For Ceramic tile floor, I may not even use bump, or just a very low setting like .1, but I use the specular map, and use the Porcelain template with shininess set to 2500 or even 5-6000. It depends on what it's looking like with the lighting and camera angle in the situation.

Put specular in the "reflection" channel. Put the bump in, and adjust to taste. I start with "1" for bump, and sometimes go down to .1 or even less, depending on the situation.

There's a glass with built-in green edge absorption in the "Transluscent" pack (Green/green absorption/use for tables)...
But what I like is to give front and back faces different than the sides and if you look at the "How Fast Are You - Official Twilight Scene - Bauhaus Lamp" scene, you can see a great approach and the perfect color for replication of this type of glass look.


For Studio lighting, just like in real life, each object needs the reflections highlighted by special reflectors, etc. You can try the free 3-point-light studio provided for licensed users along with all the free components here... check out the master list of resources.
Either way, I personally would rather find a favorite lighting studio that works for most of my scenes... which I have. It's a free one, and can be downloaded but there are many many great free HDR studios - the challenge is to find the right one, and adjust the sky brightness depending on the HDR used and the situation/camera exposure. Check the resources link above for links to HDR studios.

[JeZ]

Hey Fletch,
Thanks for the detailed reply.

( How do you know I speak french? Is my English that bad? )

I am wondering: are the the shininess and bump map based on measurable values?

I will try to raise the shininess and lower the bump. The thing is I need to somewhat figure out how the shininess works to be able to change the gloss.


I will try that 2 glass mat combo, but I feel it wont be realistic enough. I'll try it and get back to you...


I'll try those studios too...

Heres a new version of that same model. I changed the position of the model and the lights. Does real glass shelves cast shadows like that? I dont have any near to check.

Cheers.

Jerome

[Fletch]

Your info says you are from Montreal, so it would naturally follow that you may understand a word or 2 of French.

Light through or reflecting from a surface is called a "Caustic".
When you render with Easy09, caustics do not show well with sun/sky, point, or spot lights... they show best with light emitting surfaces. So, if you are rendering this scene with Easy09, be sure to light it by using triangles or rectangles painted with a very light color, like white, or off-white, or ivory, and use the light emitter template. Crank up the power from default of 100w/m2@efficiency 2.3%, and set it to something like 1000 to start, and go down or up from there, depending on the results you are getting.

Fun fact about Easy 09 and 10: number of lights in the scene does not dramatically effect render time, it may render about the same speed with 5 light emitting surfaces, or 1000. (this is an exaggeration, but the render time difference is not as great between 1 or 20 lights, as it is with Easy 1-7)

one popular way some use emitters (light emitting surfaces/light emitting materials) in studio settings is to make one large light emitting surface float above the model out of sight, and another one perhaps long and a bit thinner running behind the camera for providing reflections on the model.

You can just use the 'prelim' render setting to get a quick gauge as to general scene brightness, no need to use Easy09... depending on the complexity of the scene, etc.

LIght emitting surfaces look good in most Easy settings, actually, except the very low ones, but they do take a long time to render compared with point and spot lights.

[JeZ]

If understand well, I should be able to get green edges if I use emitters. And it would be better to use easy 10 instead.

I put my table in the Twilight Studio and used the lamp glass material on the glass shelf. Easy 9.

What do you think?

I will try right away my old glass mat with easy 10

Cheers

Jerome

[Fletch]

I think the glass there with the green edge looks fantastic?! and is simple.

Yes Easy 10 works great with any lights or materials, but clears more slowly than Easy9. If you are not in a hurry, or have a very nice computer, then Easy10 is a powerful render method.

The Flint glass template and the realistic glass template do not involve dispersion or absorption as far as I'm aware, and therefore will not likely give you that green edge you are looking for.

The green glass I mentioned from the material library that comes with Twilight should give that to you... in Easy09 with Light Emitter Materials lighting the scene... &/or with HDR lighting... I believe.

[JeZ]

Hey guys,
Heres another another attempt at my first mat study. I think it is worst, I guess I messed up the lighting... I will do again the lighting from scratch with the same mat setting and hope it will look good.

Meanwhile, I began another study. This time it is a small sideboard with painted glass panels and stainless steel foot. Definitely need more work.

Any advice would be appreciated.

Thanks.

Jerome

[Fletch]

Here are some Stainless Steel settings to try.

I use the NK Metals Material Library for most of my metals. They work great with Easy09.

Get a good Brushed Metal .jpg seamless material texture here.

Please try the Light Tent HDR images in your sperical sky. Hide all other objects so that they do not cast odd shadows onto your model.

[Fletch]

have you discovered the tonemapping settings?

[JeZ]

Hey Fletch,
Yes I know about the tonemapping option. I guess I am not very good at it...

I tried many different settings for the wood mat and it always look flatish... is it the tonemapping?

I havent been able to get rid of that strange stripe in my painted glass scene... Do you have any idea?

I guess my model is not right. I modeled 6mm glass panels and put behind it colored plane. Does it need thickness?

Cheers.

Jerome