I'm through with this. No, I'm not giving up, I just thought it might be nice to look at transmissions instead of reflections. A slightly altered scene. The big ball is now a round lump of glass. As you can see, True Ambience light can also be refracted. I've placed a colourful pole behind the glass ball to help show its optical properties. Those optics are focussing the light. You could make a magnifying glass and torment a virtual ant colony with this (if only there could be more light). When I first did this scene, it looked weird. It was like the glass ball was reflecting as well and refracting. But it didn't have any reflective properties in its material! So I disabled reflections in the optics section of the render properties dialog and it turned out OK. You'll see the weirdness later.