Stereoviewers and views

When I show someone my slides fitted to a viewer, the reactions are always similar. First: "Say, this thing is really great!" Next: "Is this old" Then: "How does it work?" I am sure that if you could see them "live" you would have the same reactions. So, I will answer each of these questions; but first, I must describe the equipment.

First of all, the 2 photographs on the slide are identical. But, this is not really the case, because in the left hand one, below, you can see very well the angle of the building, but not in the right hand one. The same observation applies for the length of the sidewalk to the right of the street. This shift is not the result of a mistake in mounting the photographic print in its cardboard frame.

Rue du Pont-Neuf vers 1860
Rue du Pont Neuf c.1860

This cardboard, yellow, is rather thick, and assures the rigidity of the combination. This permits the insertion of the slide in the viewer.

The photographic print is very thin, in order to allow the hand coloring on the back to be visible by means of the transparence of the paper. The paper is coated with albumen. One sees the colors only when viewing towards the light. The sky then appears a pale blue, and the street appears sepia colored.
The small pin holes (visible in slide 2 at the edge of the roof of Les Halles - the Market) allows the simulation of points of lights, due to a small ball of colored resin that has been deposited behind the print. A very thin layer of paper is used to protect the back of the photograph, while not absorbing much light. The resulting slide is fragile, and all too often subject to perforations and tears.

So, is it old? Nearly as old as photography itself, since the first dual lens cameras first appeared in about 1840. You did not necessarily have to have a camera, since these slides could be purchased. On the other hand, you did have to have a viewer (a stereoscope) in order to see them in 3D. Some resembled a lorgnette, other were like binoculars, and others (more deluxe) were a table top stereoscope.

This method was very much in vogue up to the second World War, all the more so in that it had become possible for individuals to make their own stereo photos.

During the 50's there were still a good number of stereo cameras available, but apparently fewer and fewer persons were interested in this technique. Was this the fault of television? Who knows!
But the principle lived on by means of systems like the View-Master for children.

Halles de Paris c.1860


The slides could be, as we have seen above, made from paper ; later they were glass, fragile, but how luminous to appreciate the 3D effect. They also could be on thick cardboard, in black and white, or colorized.

The viewers could also have a mirror underneath a cover or hood. Raising this hood, it was possible to reflect the ambient light to the inside of a stereoscope in order to illuminate the front of the slide.

Le bain de pied
Le bain de pied




Some stereoscopes


Visionneuse

Mackenstein (France) with reflecting mirror. For slides 2 1/3 X 5 inches on cardboard or glass.

Visionneuse

Unknown manufacturer, with reflecting mirror for slides 6 ¾ X 3 1/3 inches on cardboard or translucent paper.

Visionneuse

"Unis - France" with focusing. For glass plate 1 ¾ X 4 ¼ inches.


visionneuse
Modèle sans marque, avec miroir de renvoi. Pour vues 60 x 130 mm sur carton ou verre.
Visionneuse

Folding model, cardboard construction. For paper slides 6 ¾ X 3 1/3 (approximate).


Visionneuse

Stéréo-Mobile "Le Merveilleux", E.L.D. Paris. Slide 5 ½ X 3 ½ inches. E.L.D. may indicate E. Le Deley
Visionneuse

Folding stereoscope with focus. Slide approx. 4 ¾ X 2 ¼ inches.


Visionneuse

Folding stereoscope "Unis-France". Slide approx. 4 ¾ X 2 ¼ inches.


Visionneuse
Stéréoscope pliant allemand marqué Amato DRGM (donc postérieur à 1891)