Thanks for the file - that makes it a lot easier to see what is going on. When I tested it, I was assuming the rectangle was in the XZ plane and the camera was looking down on it rather than that the camera was circling in the XY plane and going upside down.
The quick fix is that you need to set the ‘Look At Up Vector’ parameter to ‘Use Up Vector’ and then set the ‘Orient Up Vector’ to 0,0,1 This makes sure that the up vector is always perpendicular to the lookat direction so that the camera doesn’t flip.
I’ve attached two versions of your file here. In the first one, I changed a few things around while I was debugging it that you might find useful. I scaled and moved the circle path rather than giving a translate in the camera and I constrained the light to the camera instead of the camera to the light. I found it a little simpler to debug the camera position when there were fewer things affecting it. Personally, I’d also reorient my scene so that the geo was in the xz plane and the camera was looking down at it so that it never had to go upside down, but that’s up to you.
In the second version I just did the fixes to the look at vector as mentioned above and left everything else alone.
I hope that helps. Let me know if you have any questions.
camera_flipping_issue_fix1.toe (16.2 KB)
camera_flipping_issue_fix2.toe (16.0 KB)