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Life-Size Images

The Jenkins Phantoscope corrected shortcomings in the camera/projector, providing a brighter image through an intermittent movement device which caused each film frame to "hesitate" at the picture aperture gate, and avoidance of film breakage with a pulley scheme to reduce tension in the film travel. The projector was powered by an electric motor and the shafts and pulleys design via cogs and gears operated in complete coordination.

The Phantoscope
Click on image for a slightly larger view.

In operation, the film is drawn, at constant speed, over an intermediate pulley and through the spring tension gate. At each revolution of the eccentric roller disk, the individual picture frame is held stationary in the gate for a short interval and then moved on. The movement is speedy—25 frames per second—so the sequential effect is smooth and the illumination is maximized. A sprocket pulley takes up the slackened film loop from the gate and it passes to the winding reel.

The Phantoscope was the first projector to produce life-size images on screens.