Figure 1 – A floating blob of water passes in front of Astronaut Chris Hadfield’s face on the International Space Station on January 27, 2014, showing how a lens inverts or rotates an image by 180 deg.. Note also the demagnification. Image from NASA and in the public domain.

The next camera optical element to consider is the lens.  Figure 1 is an image of Canadian astronaut Chris Hadfield’s floating in the International Space Station on January 27, when a spherical blob of water passes in front of him and acts like a lens.  His image is inverted and demagnified as a result of refraction. Right and left are flipped as we see them, which is to say they are preserved for the inverted image.  It is as if Hadfield’s face was rotated by 180 degrees.

From my point of view this image, posted by Hadfield on Twitter, is both whimsical and genius.  In the spirit of a picture is worth a thousand words, Figure 1 pretty much says it all!