I've noticed something a little odd with a prop I'm working on. It's a small prop - about the size of a Poser figure's hand, say, but quite detailed. When rendered in my default setup with a single infinite light, it renders completely black, as if it wasn't being lit at all. The strange thing is that if there is a single figure (not another prop) in the scene, even if my prop is nowhere near it and not parented to it, it renders fine.

A little investigation shows that the render is as expected if:

• the light is using raytrace shadows
• the light doesn't cast any shadows, or the shadow strength is turned down to about 75%
• or the object itself doesn't cast shadows
• any light other than an infinite light is used
• the prop is scaled up to about 150%

In other words, the problem only occurs if an infinite light is used with depth-mapped shadows (and the depth map size doesn't make any difference). This must be related to a combination of prop size and light shadowing, but I can't explain why. It's nothing to do with reversed normals, I've tried that.

Does anyone know why this happens and if so what to do about it? (Using Poser 6 SR2, the prop is built with Cinema 4D.)

Many thanks,
Steve

Steve