Comp technique in 'moving objects' tutorial question

[highpoly]

Up until now when I needed to render CG with shadows and reflections over a live action plate, I have been rendering with Vray material wrapper/matte surfaces to get shadow/reflections, etc.. and saving them into the alpha of sequences. I found this technique in the tutorial, although more work, to be a bit more robust and have more control.

Since I am usually passing renders off to compositors, would i just be then rendering the OBJECT and MASK vray comp textures (with filter maps and AA OFF?), as described in the tutorial, and thats all i need to give the compositor? I am guessing he/she would have to use a luma matte in their program since these images dont have alpha in them? Also, using this same techinque, how would i fit into the workflow rendering separte shadows or reflections if the compositor asked for them?

thanks, great stuff

[highpoly]

ahem..(feedback in microphone) is this thing on?? lol

If anyone is familiar with the comping technique as in vray help's 'rendering for moving objects tutorial', my questions is how to use that technique and combine it with the familiar way of splitting renders into direct lighting, GI lighting, reflections, etc. I know both techniques now but not how to use them together.

Anyone can help with this, much appreciated..

[vlado]

The Object and Mask images should be enough for compositing, yes.

You can apply the same method to any render element, not only the RGB channel (so that you can get e.g. reflection Object and reflection Mask), but it really depends on what you would like to do with these things afterwards.

Best regards,
Vlado

[highpoly]

Thanks, Vlado, I get it now...
9 times out of 10 its rendering out a CG element to be comped on a background plate with direct, GI, specular, and reflection passes (more if needed). Until now I just used matte materials with alpha when rendering stuff over background plates...