I put a shot into after effects and applied the 3D Camera Tracker effect, and when trying to select 3 points to create some text. How do I reduce the red circle "selection" thing? You can see what I mean in the photos.
I assume you're talking about the target. There should be a option for the size in the target under the advanced tab. Just click the arrow for the advanced thing, and there should be an option for the size of the target and the tracking points.
"It's all around us Neo, temporary constructs of time....."