For those who are wondering what this pin-hole candle viewing milarky is all about, here's some explanation:
Imagine the tiny hole in a piece of paper/card that light can pass through. There is also surface a few cm behind the hole. In front of the hole is an illuminated object.
Now, the light that is entering the hole from a high angle (from the top of the object) will be recieved by a low part of the surface behind the hole. Any light reflected from a lower part of that object that makes it though the hole would be recieved on a higher part of that surface.
This might give you some idea of what happens in your eye. The only reason you can see an image at all is because of this. The result is that retina receiving the image upside-down (in fact it is rotated since the same effect occurs for the left and right of the image). Your brain's interpretation of the signals from the retina develops with experience. We're effiecent at adapting as babies but can still adapt at later ages.
If you ever want to try adapting to upside-down goggles.. beware. When you've adjusted to the goggles you'll see things upside-down with the goggles OFF. It'll also mess you up a bit (sickness and confusion). Fortunately these effects will only be temporary.. unless you forget your goggles and forget that you can fall off of something above you now.
