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kiranprsad
01-24-2011, 05:00 AM
Hi Everyone, I am a 3D lighting enthusiast
I'd like to know the workflow for Maya rendering in mentalray, I have so many questions regarding this. Some of them are described here

1. How to make baked objects interact with animated objects(make them recieve shadows and lights of other animated objects)?

2. Do i get baked render passes?

3. what are the benefits of mentalray shaders and mentalray lights over standard maya shaders?

4. How to bake without reflection, specular, and animations?
I can turn off ratracing and turn off emit specular for all the lights and bake, that is good but i dont think it is a professional way.

5. When i baked the scene without reflections, and speculars. doesn't it take the same amount of time to render the reflection, specular only passes?

6. What are the benefit of tiff or tga formats over png to render?

7. Can I bake a single render layer(ex: occlussion layer only)?

8. Any way to get occlusion im miaMaterial as a render pass?

Thanks
Kiranprsad

mister3d
01-24-2011, 09:48 AM
Hi Everyone, I am a 3D lighting enthusiast
I'd like to know the workflow for Maya rendering in mentalray, I have so many questions regarding this. Some of them are described here

[QUOTE=kiranprsad]1. How to make baked objects interact with animated objects(make them recieve shadows and lights of other animated objects)?
Baked lighting is meant for fly-though animations, i.e. without moving objects. Of course, if you exclude all objects from lighting which have baked lighting and include only animated objects, you can have some kind of result, but with limitations of course. It all depends on a scene. It's clearly not an easy solution, to mix 2 kinds of lighting approaches.

2. Do i get baked render passes?
You can bake either in texture or in final gather. Not sure what the question is.

3. what are the benefits of mentalray shaders and mentalray lights over standard maya shaders?
Raytracing, better quality, more realism.

4. How to bake without reflection, specular, and animations?
I can turn off ratracing and turn off emit specular for all the lights and bake, that is good but i dont think it is a professional way.
You can't bake reflections or speculars, they are view-dependent, therefore can't be baked into texture. GI and shadows are not view-dependent.

5. When i baked the scene without reflections, and speculars. doesn't it take the same amount of time to render the reflection, specular only passes?
Reflection (not specular) takes hell a lot of time to render, and usually there are no shortcuts. You can't bake it, sometimes you can fake it with environment blurred maps, but it's a lot of hassle. Still you can render shperical environment of the scene and put it into reflection of some objects, but it will look fake on many things like floor for example.


7. Can I bake a single render layer(ex: occlussion layer only)?
You can bake occlusion into textures. You can't bake view-dependent things like refracton, reflection.

8. Any way to get occlusion im miaMaterial as a render pass?

It should output AO pass if you enable AO in arhc&design material in passes, check if it's so. For some reason I couldn't make it render in beauty pass in 3ds maz though, but it outputs as an extra pass.

kiranprsad
01-24-2011, 11:27 AM
Thanks for your useful suggessions,
I think I should clarify something

1. How to make baked objects interact with animated objects(make them recieve shadows and lights of other animated objects)?

Maya bake automatically plugs baked texture into the incandasence slot,
what about unplug that and plug it into the color slot and increase ambience?

2. Do i get baked render passes?

I mean, baked passes, like diffuse baked pass, occlusion baked pass.. etc.
we can plug them in layered texture and blend them to adjust baked texture.
i think it is a new idea,never heard.

3. what are the benefits of mentalray shaders and mentalray lights over standard maya shaders?

I found mentalray shaders are good. but we can achieve the same realism with standard shaders too. I dont know what people mean by saying more realism with mentalray shaders. I think Mentalray shaders are made to achieve real world light and shades. But it is not an artistic aproach. we will miss creativity. and become a slave of what computer gives

4. How to bake without reflection, specular, and animations?
I can turn off ratracing and turn off emit specular for all the lights and bake, that is good but i dont think it is a professional way.

5. When i baked the scene without reflections, and speculars. doesn't it take the same amount of time to render the reflection, specular only passes?

I dont know what is the right way to bake objects with reflection. One thing is we just compromise any reflections or fake it, otherwise we will end up with too much extrawork on baked shaders. So I think the best way is to forget baking if we have reflected or glossy objects

is there any way to render the reflection pass only without rendering MasterBeauty. i mean fake or something?

6. What are the visible benefits of tiff or tga formats over png to render?

I dont find any visible quality diffrence in PNG over tga or tiff. I may be wrong please clarify

7. Can I bake a single render layer(ex: occlussion layer only)?

I mean Can i bake only one render layer(other render layers whould stay unaffected, i dont want to bake them)

8. Any way to get built in occlusion in miaMaterial as a render pass?

i dont know what to do in maya

Thanks
Kiranprsad

mister3d
01-25-2011, 01:36 AM
6. What are the visible benefits of tiff or tga formats over png to render?

I dont find any visible quality diffrence in PNG over tga or tiff. I may be wrong please clarify


There is none, as both formats use lossless compression, so there won't be difference (maybe they support lossy too, but I didn't check). PNG was initially created for WEB to replace GIF format. TIFF has a lot of implementations, but not all packages support them. Even jpegs are not that similar, and some programs may not recognize jpegs from another programs. So any format may have troubles importing in another program, that's why it makes sense testing this stuff if you are planning a paid project. Different formats, especially lossless, they exist for historical reasons, as well as codecs. On this hardware in this time this was appropriate, they created this kind of format. But in 3d, openexr is a preferred format for now, if you plan compositing.

RickToxik
01-25-2011, 05:03 AM
- TIFF TGA OR PNG?

Hmm... nevermind I did not know TGA and Png supported 32 bit framebuffer. TIFF is a standard in the film industry (AVID) though with dpx. If you output render passes you should definitly learn how to use EXR I think, it's very usefull in Maya composite you can load the pass you want from the same file.

- Why Mia_x instead of Maya Shaders?

They do look better in my humble opinion. And they are unmatched if you aim for realism or want to composite with real footage... And there is also that logic in the way the shader is built that when you start to know it good, you can achieve the look you want real quick, ANY material... And they also produce quality in Mental ray faster than other shaders, they are optimized shaders.

- How to produce a AO pass in Maya mental ray?

- Enable Ambient Occlusion in the mia x material
- enable ambient occlusion in the render settings
- add an AO contribution pass to your rendered layer

kiranprsad
02-22-2011, 05:31 AM
Thanks, thanks
But in my experience, there is no relationship between mia material occlusion and oclusion in render settings. And i don't find any visible diffrence between png and tiff

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