168 THREE-DIMENSIONAL PHOTOGRAPHY“color bombardment” was a commonplace in the photographic
and motion picture industries some years ago!
The writer experienced definite color bombardment, even from
still anaglyphs when he first saw them. The discomfort rapidly
lessened, and today the anaglyph, either moving or still, provides
perfectly neutral fusion and comfortable stereo. However, the un-
comfortable color bombardment effect is constantly met with
among many people. It may be that this is something which is
subject to a developed visual skill. We have not performed nor
are we aware of any such experiments as might prove or disprove
this theory. It is simply offered as a question as yet unsettled. The
evidence might seem to suggest it, but the evidence is not suffi-
cient in quantity nor has it been subjected to a sufficiently search-
ing examination to warrant a definite statement.
The fact remains that some people view the chromatic anaglyph
comfortably, others do not.
The method described above is widely used in Europe for
periodical illustration and for the preparation of mathematical
drawings, particularly in geometry and trigonometry. A German
army periodical was printed with almost 100 percent anaglyphic
illustration. Since World War 11, in Russian Berlin, a whole
series of mathematical texts has been printed with anaglyphic
illustrations.
However, strangely enough, the continental anaglyphs are
poorly done, the ink colors have not been properly balanced to
the filters used, and there is a strong residual image where there
should be none at all. In this country we prefer to place the red
and blue inks far within the spectral cutoff of the filters, and we
achieve an almost total blanking out of the unwanted image. For
this reason, we usually print in a blue rather than green for the
one color and a fire red instead of vermilion for the other.
Amateur anaglyphs are often made. The images are either
toned with blue and pink toners (as used in the once popular
Chromatone color process), or they are printed from dye masters
in the popular dye-transfer method. In halftone printing, two en-
gravings, made with about a 30 degrees difference in angle, are
then printed in blue and red. For example, a peacock blue and
fire red have been used in the Guild laboratories.
Reproduction of AnagZyphs.-The question of restoring ana-