Hi David, Thanks for your response. There is obviously something that I am not doing right, but I can't see what. I keep getting these artifacts in the scene, like siluette cutouts of plants etc or sometimes just blank cutout slits like in the previous post. What do you think might be causing this? I changed all sorts of settings, but without any luck: http://3d-art.co.uk/www.3d-art.co.uk/Artifacts.html What is curious is that the cutout image seems to be the same, although its a different part of the scene to the previous one I posted earlier. It almost looks like a ghost image of the imported vegetation. There seems to be some conflict related to the scene content perhaps. Its a mystery.