PDA

View Full Version : Matchmoving problem... differculty getting proxy geometry aligned right for shadows.

DeepPurple
04-20-2007, 10:53 PM
Hey all, im trying to matchmove a fairly simple shot (the camera doesnt move)
but im having a hard time trying to get my proxy geometry aligned correctly.
I'm trying to place geometry over some steps and using the usebackgroud shader in maya to get shadows from my CG character.

the thing is i get the geometry to look right in the camera view, but i cant get the shadow to look right on it, are there any tutorials for this?

I've attached my maya8 scene file and a still from my clip, if somone could have a look and tell me what im doing wrong :P

Thanks in adavance :)
lazzhar
04-22-2007, 07:46 AM
There could be an oriontation problem in the camera, it's not supposed to be solved like that. The solved points are distrubted in a flat way so you cant guess where to put the geometry that represents the ground.
I never used boujou before so I cant help there. But if the camera is not moving, why bother used a 3d tracking? just match it in Maya quickly.
jussing
04-22-2007, 04:02 PM
Aye, the "move" in "matchmove" is sort of absent in this example, no tracker can "guess" how the geometry is laid out just from a still, you'll have to do something manually. You have two options:


Some trackers, like Syntheyes, will let you match a still camera, by having you add lines and points, and specifying lengths and directions.
Like Lazzhar says, just lay out a plane in Maya real quick, it's pretty easy for a simple shot like this. Maybe draw in some perspective lines in photoshop for guidance. Watch the perspective, and watch the horizon!
- Jonas
DeepPurple
04-22-2007, 07:24 PM
cheers guys, i think i cracked it, i was mainly having a problem with steps perspective.
jussing
04-22-2007, 11:45 PM
no tracker can "guess" how the geometry is laid out just from a stillWell.... it might not be far off:

http://www.fotowoosh.com/

It's still mathematically impossible to do it accurately, I'd say, but this program does a darn good job at guessing. I'd like to see the wireframes it produces.

- Jonas
CGTalk Moderation
04-22-2007, 11:45 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.