Lights turning off for particular cameras?
 

This problem has me stupified.

I have a camera and it's aiming target both on motion path curves.

I also have a spotlight with volume lighting on.

During the travel of the camera and it's aim target, it moves around the spotlight and it's volume cone.

For some reason, the light completely turns off. No light, no shadows, no light fog. It stays off for 15 frames, then comes back on again.

Yet, when I use or create another perspective camera, with all the same attributes of the one on the motion path, and place it at a similar angle and point, and at the same frame, the light is rendered as on and normal.

But when I place that created camera and it's aim target on the same motion paths with the same keyframes, the light turns itself off again.

Why would one perspective camera show the light being on, and another perspective camera show the light as being off, when the only thing different between the two is the exact angle and point of the cameras?

strange

If I'm not mistaken, cameras and lights with fog don't always work so well when they intersect. Check to see if your camera is entering the cone of the light during those 15 frames.

If you MUST have the camera go through the light fog, I sugguest making a particle system of fog, and shine a spot light on it instead of light fog.

Kind of a pain, but it should work. Then again, my theory about your problem might not be right.

Let us know.

-dann

Just discovered something this morning about the problem. I've been using 2D motion blur during the sequence. When the blur is on, the light turns off for those 15 frames (it turns off twice, both for 15 frame durations...). I turned off the 2D motion blur and.... the light came back on!

Looking into it right now...

Oh, and Dan... the camera actually doesn't intersect with the cone of volume light during the "blackouts".

Yep. 2D motion blur was the culprit. So obvious, eh?

I call that a bug.

A bug? Maybe not. Try 3D motion blur instead. Also, why are you rendering using created PERSPECTIVE cameras? My suggestion would be to create an actual camera, not a default Maya viewable camera (persp, side, front, top).

Another thing that usually works when I have rendering issues is to create a whole new scene, import the old scene into it, create a new camera and render. Can't explain why that works, but it does every time.

:beer: