It looks like you're uaing P5. If so, you need to go to the material room, select the cyclorama Figure and Material = cyc, then plug the Color_Texture node into the Ambient_Color socket and set Ambient_Value to 1. It may help also to set the Ambient_Color to white. (I used to just set the Diffuse_Value to 2 instead of 1, but ambience is more realistic). Cheers, David.