When I have refractions turned off on the glass shader on the lens, everything looks good (except for the lack of refraction, obviously). But when refractions are turned on, every shader inside it goes crazy. For some reason, when rendering, it turns the reflectivity of everything behind that lens up to 100% (like a polished chrome shader, essentially). Just to clarify: The material settings doesn't change, it's just the looks of them in the render that is out of whack.
At first, I thought it might be a problem with the trace depth, so I pumped that up way high, both in the render globals and in the individual materials, but that didn't help even the slightest.
So, how do I whip my shaders into behaving like they should?
Three screenshots, first with the lid on, second with the lid off, third with the lens of the eye turned off. It's very obvious that something is going on, if you look at the backside of the clock. The actual clockwork is covered by a glass window, and as you can see, the inside of the casing looks completely different from the outside, 100% reflective.