Multi-Pass Rendering?

[Laconic]

Hi!

 

I'm taking a visual effects class where MAYA is used for examples. The teacher allows us to use any CG program we'd like and I like A:M MUCH more.

 

For our projects, the instructor suggested that we make layered passes of any render (i.e. Specular Pass, Shadow Pass, Diffuse Pass) so that they can be adjusted separately in a program like After Effects without having to re-render the entire composite (Maya can do this). He says this is how the industry is moving.

 

My question is: Can A:M render in separate passes, as described above? Specular pass, Diffuse pass, Shadow pass, Ambient pass, etc.

 

Any help or links to tutorials would be appreciated.

 

T

[Fuchur]

That has been a featurerequest for quite a while because it is quite comon in the industry to do that but as far as I know: No, A:M cant...

BUT there is a solution for some of the passes. You should have a look at the shaders and at the object-properties. There some things can be setted which can help. For example: Rendering shadows only, etc...

Another thing you should search for is the EXR-format, which can help much too... For example you can edit the lights seperatly without rerendering it, etc.

 

I assume the following: A:M isnt capable of this native because it is meant to do everything "in a box" and the other approach needs to have another composition-programm...

 

I may be wrong so... maybe it is possible now?

 

*Fuchur*

[KenH]

No, Multipass doesn't do this. It increases the quality of the image with a higher setting.

[John Bigboote]

That is a powerful feature...does'nt the new 'composite' feature sort of do this using .exr buffers?

 

This is how Division X (a company I work with) is able to get their photorealism... http://www.gracewild.com/divisionx/index.html

[Fuchur]

In other programms this is called Passes-Rendering... Multipass-Rendering means to render the image several times without antialising and than combine the images to get nice smooth edges... but what he is talking about is passesrendering which is a way to render only for example the specular-spots in the image and nothing more... the rest of the pass is transparent. (like the alpha-channel in a tga but ONLY with the spots visible...)

 

>>That is a powerful feature...does'nt the new 'composite' feature sort of do this using .exr buffers?

It is a start, but it does another thing... the buffers separate different lights, etc. but not the effects itself. The cool thing about it: You can very easy change for example the specular-color in the post-production...

 

 

*Fuchur*

[NancyGormezano]

A very crude and clumsy way of using A:M to do this might be to change the settings on the lights in the scene to just have specularity set on (render), then only diffuse (render), then shadows only (render), flat shaded toon(render) - then combine the renders in AE -

 

sounds like a lotta work for ??? - and sounds like composite is more what you might be looking for.

[youngman]

Hi Laconic,

I hope this might be of some help.

Soulcage dept have been making some fantastic commercials with A:M over the years and in one post on these forums explained a little on how they went about doing seperate passes and then combining them in a compositing program.

 

http://www.hash.com/forums/index.php?showt...ulcage&st=0

 

Check out page three of the post to see the example.

 

Jay

[zandoriastudios]

You can render with buffers. Then load the .exr sequence, and export the buffers individually.