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Mocha and Element 3d Problem
Mocha and Element 3d Problem
by Guillaume d'Harcourt on May 28, 2017 at 1:13:29 pm

Hi ! First of all I'm french so I apologise for the writting mistake I will certainly do.

So, I'm making a short film for an optional test for my school's end exam, and I want to add a 3D object on a wall.
Here's a screenshoot of my original shoot :

So, I oponed my shoot in mocha AE, I Tracked the paper that I want to replace, and I export the track as "After Effect transform Data", and I applyed those data to a null object.

Than, I created my 3D object using Element 3D , and I use some expression to link my 3D object's data to my null's one.

But, here's what I get as a result :

Looks like my 3D object isnt link quite well, but I don't know what to do. Do you guys have an idea ?

Thank you very much

Re: Mocha and Element 3d Problem
by Mark Whitney on May 31, 2017 at 5:10:16 pm

Does it track with poster correctly otherwise or is it simply offset?

If not, take a look at this tutorial.

Pretty sure it's this one but possibly the next. Anyway, in it Andrew discusses using the use of the Utilities TAB in Element 3D to generate the 2D & 3D positions for nulls used within the E3D co-ordinate system. I suspect that's what you need to understand to get this to work with E3D items.

This one from Imagineer Systems may be of interest too.

Re: Mocha and Element 3d Problem
by Cassius Marques on May 31, 2017 at 6:21:18 pm

I won't say that you can do that way but try to consider this: In that shot, does the paper thats stuck on the wall moves? Or the camera that's capturing it does?

So if you're still choosing to track the paper instead of the camera, just make sure you're getting data that encompasses all axis, not just X & Y. Or X,Y and scale. From what I can see in the SS, you're disregarding scale and you're probably just not compensating for the point of origin of your mesh.

Cassius Marques