Black render after camera switch.

I have an animation with a moving camera which was working fine. I created a second camera for some still shots and set it in the scene tab, the stills have rendered ok.

Then I switched back to the moving camera to do some more work and the render is just black. Switching to either camera now produces a black image. I haven’t changed anything else.

I’ve been through the usual things that I forget, nothing is set to not render, the render layers are unchanged, my scene is unchanged.

Any ideas?

Thanks.

No demo blend file supplied !! Please supply all necessary files etc

Just as an update, I couldn’t find a single setting that was wrong.

I created a new camera which worked fine. I swapped back to the original camera and that also worked fine. So I have no idea how I’d messed things up, but simply creating a new camera solved the problem. I can only guess some handle or link had gone awry and creating a new camera synced things back together.