I'm animating a simple fly-through of a tunnel. I've got the tunnel modelled, and I've got a motion path set through the tunnel that the camera flies along. Everything works great, until I try to render it. When I render, sometimes some of the frames of the animation (like the attached frame) have large black areas in them. Most of the frames do not, however. Why is this? Could it be that the camera is sticking partially out of the tunnel? When I watch the camera travel along the path in the assemble room, it appears to be totally within the tunnel no matter what angle I look at it from.

A note on the render: I haven't even begun doing lighting yet, so I just put a criss-crossing glow texture on the tunnel to make it easier to see what the tunnel looks like and where the frame didn't render.
Thanks for your help!

Yeah I would say thats internal geometry we are seeing blocking part of the camera, although usually thats the whole camera, try rendering the same frame, and then move the camera a little to see if that effects it at all. The only other option is...which I doubt, just the way it looks, is reversed normals in the geometry can make weird appearances like that, though this is to blunt and sharp of a change to be that I think. Let us know what happens. Brian

i don't have any experience with tunnel fly-through's, but the fact that the un-rendered area is perfectly vertical. not even slightly diagonal looks unlike geometry to me. if you render out an image sequence of this, find a bogus frame, then go back to your sequencer in carrara, set the time to frames, you should be able to get to the exact frame that you're looking for. then try to test render just that frame to see what happens, and or look for objects in the way. might also be usefull to figure out where in the tunnel this occurs and render the animation from a camera outside the tunnel to see if anything comes flying through the tunnel wall. good luck.

I've also run across some weird things when rendering animations with the camera flying along a path. I would sugest 2 things: Set-up your flythrough as a bunch of keyframes instead and see what happens. It takes more work tweaking the keys, but I think it is more relyable. And, rendering out as an image sequence, (like pixelicious said.) Then you can see exactly where the weirdness is. You may also find that it goes away! I have had some strange things happen when rendered as an animation that disapeared when rendered to an image sequence. It's also safer if anything happens with your computer during the render. An animation can be corrupted if C crashes, but an image sequence is good up to the frame that crashes, AND you get the bonus of knowing what frame screwed up! :>

I've seen it in other programs. I wouldn't be suprised if your camera is cutting off because of the camera's "size". Can one scale the camera size in carrara? I know that this is possible in Bryce. (I havent tried working with the camera and lights yet in Carrara, and after a respit od a couple months I'm still trying to get a handle on the basics). Otherwise you may try rescaling your 'tunnel' larger so that the camera 'fits' better.

yes you can rescale the camera in Carrara :) in the Properties tray, select the camera, then go to the Motion/Transform tab, you'll see you can rescale it there at the bottom. take care, Robin

Thank you all for your help! Unfortunately, none of your many suggestions were the answer. An Eovia representative, however, quickly explained to me what the problem was: parts of the geometry were indeed being clipped, but the solution was to simply render it in the global illuminations renderer. That solved the problem instantly! So, if you ever have a similar problem, just try a different renderer. Thanks again for all of your help!