I'm trying to render an eye. There's an inner object with the textures and a slightly larger object with a bulged front to simulate the cornea with a glass shader assigned to it.
Of course this cornea shouldn't cast a shadow, but whenever I uncheck "cast shadows" of the object, I lose the highlight. Reflections are there. When I turn "cast shadows" on, the highlights are there, but it looks quite dark. No matter, if I render with the standard renderer or the path tracer.