Ahh.. my favourite subject
One image of a world behind the mirror is on the site, it is the one of the sailing boat in the 'what' section.
(click on lucid? scroll to "high lucidity" and click on the word "clear")
that was the most vivid lucid dream i ever had. I had stepped through my bedroom mirror, and came into a little room. It was some kind of elevator also. When i looked out of the window I saw i was in a very high white building. Everything was so clear. I could see very far in the distance. (the image didn't blur like it does in real life). In the distance was an ocean of the clearest blue you can imagine. In there was this pirate ship i tried to capture in the painting. I painted this almost directly when i awoke from that dream.
about the worlds.. well it is like this, when you have stepped through, you know you are lucid and everything is not real. So you go out exploring (at least i do).
I mean, when you become lucid you are still in the dream you were before. When you have stepped through the mirror it is like going to explore another world. You don't know where you will end up so everything is new.
of course i've also stepped through once and found myself in the clothes closet which was behind it irl. (and yes, i was still dreaming :))
just try it and you will see!
Q"You can only fly when you have both feet firmly on the ground..."