CHAPTER 11ANAGLYPHSINCE THE DAWN of stereo there has been an endless search for
S some method whereby stereograms of unlimited size could
be seen. The first solution was the original anaglyph. Today this
is known as the chromatic anaglyph, because we have a superior
new type, one which approaches the ideal. This is the polarization
anaglyph, which is more commonly known as the Vectograph.
It is known that the stereo impulse depends upon the simul-
taneous stimulation of the two eyes by two different stimuli. It
is also desirable that these two stimuli should be placed so that
no excessively abnormal vergence is needed to view them.
It is also known that in additive color mixing, any pair of com-
plementary colors will produce white, and that this theory is borne
out in practice to a considerable degree. It is further known that
in subtractive mixing, two complementaries will produce black.
It would seem, therefore, that if a mixture, for example, of
orange-red and blue-green will produce white, the separate stimu-
lation of the two eyes by red and green simultaneously should
produce a sensation of white through stereo fusion. If this is true,
then a red picture and a green one presented separately to the
two eyes should produce an achromatic image (neutral or white).
If the red image is blanked out by a red filter and the green by a
green filter it should produce the necessary stereo differentiation.
Thus, the first anaglyph consisted of a stereogram made by
printing a picture in red, and another picture in green was
printed directly over it. This was viewed through a pair of “spec-
tacles” containing one red and one green lens.
The result was mixed. To some people there was an excellent
stereo effect; to others there was a stereo relief visible but upon a
background of alternating flashes of red and green. This latter is
said to be a visual-pathologic condition, but if so it is widespread.
The anaglyphic motion picture was first presented publicly three
or four decades ago and was withdrawn because of the complaint
from those who suffered headaches resulting from the color alter-
nation. In fact, this phenomenon was so prevalent that its name,
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