Jinx said

> I was blowing myself kisses in the mirror today, as is my wont,
> when I got to wondering why mirrors reflect left to right but not
> up to down. I mean, I'm OK with them the way they are, I couldn't
> see myself in a house without mirrors (ha ha). I've looked for an
> answer but no luck. This "explanation" at How Stuff Works is a
> pretty sorry attempt. In fact it dodges the question altogether


As others have noted - mirror does nothing and just passes things straight
back as it "sees them" (as you'd hope) - how you interpret this is all in
your mind.

BUT

I have a device sold as a through door viewer (no, you need a hole) to see
people standing outside.

The device is tubular in shape.
There is a "right way up" when mounting this
If you look though this and rotate it 90 degrees the image turns 180
degrees.
Rotate it 180 degrees and the image turns 360 degrees to be right way up
again.
It's an optical image rotator with a gain of 2 times !!!

No amount of lense processing seemed to explain this.
I had to pull it apart to see how it worked.
It's almost obvious once you see how.

Anyone seen this effect?

Would anyone who hasn't seen it before or cheated by pulling one apart care
to venture how it may work?
Be prepared to waste some time and brain power.
A useful education.

:-)



Russell McMahon

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