While I wait, let me educate. With a biconvex lens (or bowl) any object further than the lens (or bowl) focal length will be upside down. That's physics.

We can actually make it not do that, but it will no longer be an accurate glass+water simulation.

For most purposes, we can generally say that the focal length is twice the radius of curvature. For something that is nearly a sphere, the distance is just one radius.

So - if you have a 10 inch glass globe, everything more than 20 inches from its center is upside down.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)