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aanimate
09-28-2006, 06:52 PM
HI all!

I have a shot of a hand holding an object and camera moves around the hand. I need to take out the real object and put a cg object in place.

I could redo the shot with a blue or green object to make it easier.

I am pretty new to this task, but I can do matchmoving. My only bump right now is how to make sure I overlap the original object with new one and don't have any artifacts on the edges.



I tried using a green object with the same size as my cg object but still it is not working out too well.

Probably I can do rotoscoping, by wonder if there any easier way to accomplish the task.

If anyone has a suggestion I will really appreciate it.

Thank you!
arvid
10-03-2006, 09:15 AM
If you want a CG object there, don't put any real object there at all. Track the background (ie. the hand) and composite the 3D-object on top of it. Why would you need anything else, it would just create extra work and lots of problem :)
Tygerboy
10-15-2006, 10:55 PM
Yep, as arvid said, a lot easier with empty hand.

Just popped into my mind, that you could enhance your workflow by using a white marker to draw small dots to your fingertips to make the tracking easier. I guess that with certain backgrounds this type of method would be useless though...

Anyway would be a fun experiment! :D

Good luck.
Kai01W
10-16-2006, 12:01 PM
I disagree about shooting with empty hand. An object can make traking more precise and it might result in a more natural grip of the hand. Plus it might give you natural shadows on the hand. Just make sure the object is (a little) smaller than the one you want to put in (from all perspectives).

-k
Aruna
10-17-2006, 03:32 AM
Depending on the context of the shot, I would do either or. I did a CG object in hand a long time ago. You can take a look at it on my 2003 Reel (http://www.digitalgypsy.com/movies/aruna.DEMO.reel.2003.avi) (26mb avi). It's the shot where the guy holds a tennis ball and it levitates out of his hand and turns into the world. There's also a quick breakdown of that shot later in the reel. Basically it's a still of a hand and a CG tennis ball, comped together with various passes. For my shot in question, it was easier to shoot without an object. I added in hand float after the fact. Depending on the necessity of interaction between both hand and object, you may find it necessary to have a placehold object for the actor to reference. Again, it depends on the context of the shot and the complexity of any camera motion.

Good luck.
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