The name anamorphosis has been given to two kinds of pictures
distorted according to a certain law, and which are of such a
grotesque appearance that it is often impossible to recognize the
subject of them; while viewed with proper apparatus they appear as
perfectly correct images. One kind is designed to be viewed by
reflection and the other is reconstituted by means of a special rotary
apparatus.
[Illustration: FIG. 8.--ANAMORPHOSIS VIEWED IN CONVEX CYLINDRICAL
MIRROR.[1]]
[1] From "Experimental Science." Published by Munn & Co., New York.
Until quite recently, these pictures were drawn approximately from the
reflection of the object as seen in a convex mirror, the position of
which was indicated on the drawing and which restored it to its real
form. M. Fenant conceived the idea of employing photography for
obtaining these pictures. Fig. 9 reproduces a photo-anamorphosis from
a negative by M. Fenant. If a cylindrical mirror be placed on the
black circle shown in the reproduction the photograph will appear in
its original form. Our illustration represents a portrait, although
the features are barely recognizable. Similar pictures may be obtained
by photographing the drawing or subject reflected in a cylindrical
concave mirror placed perpendicularly.
[Illustration: FIG. 9.--A PHOTO-ANAMORPHOSIS.]
The second kind of anamorphosis is produced by the distortion of the
picture in the sense of one of its dimensions. To reconstruct it, it
is caused to rotate rapidly, at the same time that a disc, perforated
with a slit through which the picture is viewed, is rotated in front
of it at a slightly different speed.
The apparatus invented by M. Linde for producing the anamorphosis is
shown in Figs. 10 and 11. _G_ is a camera provided with a revolving
plate-holder, _T H_ are revolving discs the movement of which is made
to bear a certain relation to that of the plate-holder by means of the
band F and the pulleys _D D_. The whole is set in operation by a piece
of clockwork and the cord _F_. _A_ is the axis of the camera, _B_ that
of the plate-holder, and _C_ that of the revolving disc. On this disc
is fixed the picture from which it is desired to make an anamorphosis.
The relative motions are so regulated that when the plate-holder has
made a complete revolution the disc has turned through an angle of 60
to 80 degrees in the opposite direction. Between the plate-holder and
the lens is a diaphragm pierced with a slit about 10 millimetres wide.
The action of the light on the plate takes place through this slit.
The negative obtained, prints are made upon plain salted paper and
rendered transparent with wax or vaseline. These pictures can be
viewed in the ordinary apparatus used for showing anamorphoses of this
kind. The print is fastened to a revolving apparatus and in front of
it is another disc painted black and provided with a number of slits.
The latter revolves at one-fourth the speed of the picture, and the
image when viewed through the slit resumes its normal proportions.
[Illustration: FIGS. 10 AND 11.--LINDE'S APPARATUS FOR
PHOTO-ANAMORPHOSIS.]