3d Camera -> 2d Comp

[pushat]

hello fellows,

first of all, i do not know if this is the appropriate forum to post this question, so if its wrong, i do apologize!

im just curious to know what kind of workflow you guys follow when doing camera animation in your 3d app and then comp it in after effects, shake, what have you..
i have a kinda complex maya scene, with a lot of flying elements, a car animation, particles and so on.. and ive also got an animated camera. i have to comp the scene in after effects later on, but im unsure of how to do it. If i render the whole scene as a sequence, i dont get any camera information nor keyframes. and my whole scene would be like a 2d plane that wouldnt be flexible at all. like, if i was suppose to add additional elements in after effects later on, the only way around was to track my 3d and apply it to my elements.. im pretty sure that that way around isnt the correct way around. So i'm very curious to know how you guys go about taking a 3d scene with camera animation and make it compatible for comp.

i'm using maya. i tried to import my camera information, via bake simulation, and then import the .ma file, but that didnt make any sense in after effects. well, i got my camera information, but it all went wrong.

i would be pleased if any of you guys would bother to answer me.
hopefully you understand me, sorry about my english skills.

thanks in advance

[joojaa]

QUOTE(pushaT @ 10/14/07, 02:45 PM) [snapback]274827[/snapback]
i have a kinda complex maya scene, with a lot of flying elements, a car animation, particles and so on.. and ive also got an animated camera. i have to comp the scene in after effects later on, but im unsure of how to do it. If i render the whole scene as a sequence, i dont get any camera information nor keyframes.

Well, if you could do everything in 2d you wouldn't do 3d. Its a trade off, because rendering a 3d scene is heavy you'd collapse it down to pre rendered form. Thsi would allow you to have SOME control over the porcess, its a loose some gain some situation. Usually the design is that the amount of elements is fixed at this stage, its just the combination of the elements you'd change. The comp software is no longer in 3d land so having it get the 3d animation fo the camera is mostly half meaningless because you couldnt add a element that matches the comp anyway. If you could then again you wouldnt be doing that step at all.

Its not like yoyu cant just read the 3d animation into your comp software, you can no biggie. but proble,m is that its often completely useless anyway.

Trick is to design the effect you want ahead of time so you dont comit to rendering until you know exactly what you want, and then maybe output a set of masks for things like color changing (object id channels and render component chanels, such as aspecular ambient occlusion) form your render these are flat yes thets the idea. (but yes you can come back to 3d and render a additional plate, if its not ray tracing its probably quite fast but you'd only do this ever if you really really screwed up)

So the idea is that you render out the same image to MANY planes. But the true answer is if you dont know how to comp your stuff its pretty sure you dont need it then at all.

Whenever i render a private job i allways output following channesl unless i need something special. (from one render i hardly ever use render layers for anything except whan i truly need to split GEOMETRY):

Ambient, Ambient occlusion, Object ID (its for doing any track later by substituting it with a simple color key instead), coverage, z (its free so why not and combined with coverage allows for goo dzcomp, but wont work on ae since its not really good 3d comp software), UV, motion vectors, reflection, refraction, diffuse (per light), specular (per light), shadow (per light), env refl.

This allows me to make pretty good color matching and good starting point to adding stuff aferwards, wich i wouldnt do unless i screwed up and have no choice. MMostly comp is about the images natch not the ability to add stuff later.