Chapter II

Andy Warhol, creature of the black lagoon and comics

They have all used a stereo process called anaglyph. Andy Warhol produced a 3D anaglyph Frankenstein in 1970.
Creature of the black lagoon is one of the most popular 3D anaglyph movie.
From time to time, comics use that process too.
(Notice that, in that last case, each stereo pair is hand made . . .)
Unfortunately, most of those realizations suffer from terrible defects.
They often have as a result an audience that is disgusted from stereo.
The fact is that the anaglyph process by itself is not a bad one but is difficult to apply with optical systems.
Let's analyze those old results and have a close look to the "theory".
Let's see how to apply it correctly with a computer.

In comics, left and right images are printed, one with blue ink and the other with red ink.
Looking with red-blue anaglyph glasses, you can see monsters springing from the page.
In movies, red and blue filters are added to the cameras as well as the audience wearing their own red-blue glasses.
Red and blue are used as they are opposite colors: you cannot see through a red filter what you can see through a blue one, and the reverse is true.
The stereo separation is correct for each eye but the stereo image is black and white.

If you're aware about computer image formats, when reading "red-blue" you've probably the temptation to insert "green" to read "red-green-blue".
Congratulations, you've found the first step to the solution.