View Full Version : render passes

01 January 2010, 12:53 PM
Hi to all,

I have a scene lighting done in mental ray with one mr area spot for Sun.
2 mr omni as filling light.
skylight for final gather and indirect illumination.

now i want to render it in passes.
But i don't know how many minimum passes needed for a good composition.
and second is how to arrange all passes and set their blending modes and layer settings in Photoshop/AFX.

If anyone has some sort of PSD file done, can mail me.
Even a tutorial is also welcome
Please help me .
Its very urgent.

Thanks in Advance

01 January 2010, 11:44 PM
Look in the mental ray "production shaders" help file, it has everything explained about passes and how to combine them.

02 February 2010, 07:18 AM
The idea is simple: you use as many "passes" as you decide you need!

Each "pass" is simply your way of producing one of many distinct parts of the image. You break the shot down into however-many of these, and the payoff becomes ... "if you've already done it once, you don't have to do it again."

"Passes" can isolate both parts of an image, and distinct visual characteristics of those parts. Really, "whatever you decide you want to isolate." Whatever saves you the most time and gives you the most flexibility.

Think of it like an audio engineer who's doing a big recording-session for a new hit song. What they do is to record one thing at a time, isolating everything into distinct "tracks." Then they clean-up those tracks, one by one, and then they "mix down" everything until they wind up with the finished recording. Because everything's isolated from everything else, they can "tweak" the mix to get it just the way they want it. If one track has a flaw, that one track can (in isolation) be patched, hacked ;), repaired or replaced.

Exactly the same principle! "Render passes" are simply the process of producing the individual "tracks" of material, each one isolated from all the others, so that the shot can be "mixed down."

02 February 2010, 09:25 AM
Thanks vbmenu_register("postmenu_6330626", true); vbmenu_register("postmenu_6330626", true); mister3d ( and sundialsvc4 (

this is very informative.
but i am still looking for some practical example.
Hope i may get what i am looking for

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02 February 2010, 09:25 AM
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