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ODoul
11-07-2005, 11:36 PM
Before I go trudging thru the manual trying to find the answer to this question, I thought I'd ask to see if anyone knows if it is even possible to do using multi-pass render.

I'd like to separate a render out into 2 layers, a foreground layer and a background layer, I realize that I can do this using 2 separate renders and an alpha channel but I'd like to do it in one render.

Can this be done with multi-pass rendering?

Thanks.

Hilt
11-07-2005, 11:48 PM
Can this be done with multi-pass rendering?

I think that's the whole meaning of multipass.
The manual is your friend here, but multi-pass works pretty well with pure commmon sense also.

ODoul
11-07-2005, 11:51 PM
Exactly the kind of response I was expecting. The manuals say plenty about rendering separate "channels" ie ... shadows, highlights, etc but make no mention of rendering layers.

dann_stubbs
11-07-2005, 11:54 PM
Before I go trudging thru the manual trying to find the answer to this question, I thought I'd ask to see if anyone knows if it is even possible to do using multi-pass render.

I'd like to separate a render out into 2 layers, a foreground layer and a background layer, I realize that I can do this using 2 separate renders and an alpha channel but I'd like to do it in one render.

Can this be done with multi-pass rendering?

Thanks.

if i understand right i think you can assign a compositing tag and then apply the object buffers to each "front" and "back" that you want.

i think if you assign multiple objects (or a group of "front" and "back") to say the object channel you will get what you are thinking.

how i am interpreting this is how maya handels layers and render layers where you can assign front objects to one layer and back objects to another and then render the respective front and back layers - so i'm not sure if i'm translating to c4d correctly.

dann

ODoul
11-07-2005, 11:58 PM
Thank you very much Dan, that is what I was hoping for. An answer to my question.

ODoul
11-08-2005, 05:10 AM
Even with Hilt's super helpful advice, I still can't get it to work. I must be doing something wrong but I'm following the manual's somewhat vague instructions on the topic (page 692). Evidently the manual doesn't like me and we can't be friends ...

TimC
11-08-2005, 01:37 PM
all the objects you want in the foreground layer. Add a comp tag to them (or a group of them), then activate object buffer. Set it to no.1.

all the background objects, do the same but this time use no.2

In the multipass settings, add RGBA image, and add object buffer twice. Set the first to 1 and the second to 2.

When you render you will have your RGBA render, and 2 other files which are your object buffers. You can then either load these buffers into the alpha channel in psd to then load them as a selection, or you can use them as mattes in a program like after effects.

HTH
TimC

ODoul
11-08-2005, 02:10 PM
Fantastic! Thanks TimC. Just out of curiosity, is this something that is covered in the manual because I sure couldn't find anything as specific as your explanation.

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