Shape Allows you to select of the default the shape: square, sphere, disk and cylinder. (...or a custom mesh geometry...) Visible to Camera Makes the light source visible to the camera (a.k.a primary rays). From left to right: off (default) and on. Two Sided When enabled, the area light will illuminate from both sides. Note that this has no effect with the sphere shaped area light. From left to right: off (default) and on.