Camera Stereoscopic Slides
Have you ever looked through a stereoscope at a pair of pictures and noted how marvelously everything stands out in relief? As you probably know, two picture almost identically alike are needed in order to provide the stereoscopic effect. When the pictures are made by photography, two exposures are necessary, one taken with the lens in the position of your left eye and the other with the lens moved to the position of your right eye.
If you have a box camera, it is quite an easy matter to make stereoscopic slides which, possessing a personal touch, will interest you a great deal more than slides that are bought. This is how you set to work: First, take a piece of paper and cut it to double the size of the bottom of the cinema, as indicated in the diagram. Then, when you want to take a stereoscopic picture, spread out the paper on something motionless and flat, place the camera on one of the halves of the paper and make an exposure. Follow this with a second exposure while the camera reposes on the other half of the paper. Of course, the paper must not move during the work, so it will be advisable to pin or weight it down.
If you should possess two box cameras exactly alike or you are in the position to borrow a second camera from a friend, strap the two together, side by side, and make both the exposures simultaneously. Whether you use one camera twice, or two separate cameras, the results will be the same. You will have two pictures, seen by the lens from positions that were about as far apart as are your two eyes. That is why the stereoscopic effect is produced.
In trimming the pictures, be very careful to see that you cut them horizontally alike and, when mounting, that you place them on the card in the same relative position as they appeared to the lens of the camera.