5/22/2012

Learning New Techniques: mia_materialXpasses and linear workflow

Heeeeey it's being a long time since last time I made a post here!
Like a month ago or something. A lot of things happened since I graduated from Lost Boys.
I had to go back to my country to fix some issues with my passport, but I came back to Vancouver BC :D.
I got a job offer as a Junior CG Generalist in a great company called Goldtooth Creative, and I am learning a lot of new and cool stuff there.

I might not have so much time to work on my own personal projects, but still, whenever I have a couple hours or so I try to keep learning at home.
Although the fact that summer and good weather is arriving to Vancouver (aka Raincouver)
makes me wanna stop being in front of my computer, go out and enjoy the good weather (which I think is something naturally normal after a looooong dark and gloomy winter :P)
Anyway, so one of the most conflicts that I had when I started working, is that I didn't know how to use many of the production tools and workflow that Maya offers.
To be able to integrate in a good way in the place, I would have to learn all of it.
So far I have being using Blinn Shaders with custom maps, which gave me great results and nice looking renders, but I would have to go one step further and start using the mia_MaterialX and other production shaders and tools, so I could adapt better to a new professional workflow.
Plus, I wanted to learn this techniques, but I just felt too lazy go go with it, and normally when I get used to do things one way I feel even more lazy to learn different techniques.
So I actually felt a bit frustrated when I knew I would have to start all over again, but in a couple of days I started feeling more comfortable using the mia_material and working in Linear workflow. And I liked the results that I was getting.
Pretty cool stuff! I also learn how to take the maximum advantage of HDR Image based Lighting using the Smart IBL. (go here for more info)
I thought it would be hard as hell but it is actually no that bad. The cool thing of the mia_MaterialX is that uses physically accurate parameters to calculate how the light acts on the surface and the result are incredibly photo realistic!
As I said before, I could get similar results using a Blinn and custom Maps for each parameter (i.e. Diffuse, Specular, Eccentricity, Reflectivity), and Finally I would end up with a complex shader that works ok, but takes time to render since there are so many connections going on in the shading network. With mia_Material I have the feeling that everything runs faster because it has built-in features like Ambient Occlusion or a BRDF curve built in for the level of reflectivity in different angles of the surface.
This actually was a bit confusing for me at the beginning because I was building a simpler shading network which is more accurate in render time.
And the best of al is that I can still use custom utility nodes like the Sampler Info in order to get different effects.

So I am very excited about all of this new techniques that I am learning.
Now I do have my opinion about this way to work. I order to achieve a photo real look (say, for CG integration and photo realistic VFX) is a very good thing to use this tools because are physically correct. But, it doesn't have to be the only solution. I think it is very cool to explore different materials and ways to use different lights and of course, use your own creativity to achieve different styles for personal work. Or even combine all the techniques could be interesting, I don't know!!!
At the end what we want is to make beautiful images right?
That's why I love CG, there is always sooo many things to learn...

This is a super simple scene which I was playing with yesterday. I just wanted to get a bit more familiar with the mia_MaterialX and try different shading options.

 

mia_MaterialX with custom input connections for the metal can


I also used Final Gather combined with Global Illumination. GI is something that I really don't know how to use it, honestly. I watched a couple of tutorials, and basically I know how to make a light to spit photons and play with the quality in the Render Settings. However I hear we don't use GI so much for animations. But since this is just a still image I just wanted to give it a try.
So in the whole scene I have an Area Light for the window with a cool tone, and a Warm Spot Light in about 45 degrees in relationship with the camera. Both of them emitting photons. Then I have a blurred small HDR image of an empty room and a bigger and sharp version of it used as the reflection map. Both of them are connected into the IBL node (as a texture) through a production node called mip_rayswitch. And my lights are working...well, pretty cool if you ask me.



mip_rayswitch in action!!





Well so that's the result of my little research I did. I wanted to have no post on it, but , what can I say, Compositing and post-production in general is such a beautiful process so I can't ignore it.
So I just added a bit of glow, grain, chromatic aberration and vignette just to get a better photographic effect. And that is the result of it.
My first steps with Mental Ray's mia_MaterialX and 32 bit Linear Workflow!!
I hope you find this post interesting and I hope I'll keep learning a lot of new techniques!
Thanks for visiting my blog!

1 comment:

  1. love it man , just did not understan the ramps that you use.

    looks great
    congrats
    wev

    ReplyDelete