Creating Null from 3D tracked point

[j611obrien]

Hello All,

I'm a novice with After Effects so your patience with my ignorance is greatly appreciated. I am trying to attach some nulls to 5 separate points on my footage. From each of these 5 points, I wish to generate a beam that leads to some text. I have analyzed the 3D tracking camera, clicked on tracking point(s) and selected "Create Null and Camera". I've done this before without issue in other projects but for some reason, the null object is not being attached to the item and instead the null is placed outside of my 1920X1080 composition space. Screen shots below.

Any ideas why this happening?

[Szalam]

Something might be screwy with your track. What sort of lens size is it guessing?

[j611obrien]

Hello - where would I find that information? Thanks!!

[j611obrien]

Fixed! 3D Tracker Camera was not selected. It was somehow put on "active camera".

[j611obrien]

Well, I guess it wasn't quite that easy. The nulls only stay affixed to their points when the 3D tracked camera is selected. However, when I pick whip the beam to the starting and ending point it seemingly only works when active camera is selected...... but then the nulls aren't in the intended spots.

[Szalam]

The camera created with the 3d camera tracker should be the active camera. Make sure you don't have any other cameras in your composition.

[j611obrien · Accepted solution]

Okay - I have found a solution. The problem with my clip is that it was imported from Premiere Pro. The footage was reversed in Premiere Pro before bringing it over which I guess can cause issues. My solution was to export the reversed clip as an mp4, import it back into Premiere Pro, then "Replace with after effects clip". This allowed me to keep my 3D track my 3d footage on the active camera.