Multi-Image

Multi-image is the now largely obsolete practice and business of using 35 mm slides (diapositives) projected by single or multiple slide projectors onto one or more screens in synchronization with an audio voice-over or music track. Multi-image productions are also known as multi-image slide presentations, slide shows and diaporamas and are a specific form of multimedia or audio-visual production.

One of the hallmarks of multi-image was the use of the wide screen panorama. Precisely overlapping slides were placed in slide mounts with soft-edge density masks; when the resulting images were projected, the images would blend seamlessly on the screen to create the panorama. By cutting and dissolving between images in the projectors, animation effects were created in the panorama format.

The term multi-image is sometimes used to describe digital photo image computer programs that combine or change images on-screen, for photo montages, and image stitching.

Multi-image presentations were a unique form of communication to audiences of various sizes, to meet a variety of communication and entertainment needs. The use of projected photographic images such as lantern slides for entertainment and instruction dates to the early 1800s. Others, such as L. Frank Baum had a traveling show (1908) that included slides, film, and actors describing the land of Oz. Throughout the years improvements in technology took place and applications for multi-image continued to expand. During the 1960s, automated synchronized audio and slides modules became more common and found use in instructional environments.

In general, multi-image can be defined as being:

Multi-image as a business thrived during the 1970s and 1980s. Multi-image presentations ranged from single projector shows run by projector-viewer to large events for business meetings and conventions where multiple shows would be presented and often were rear-projected by 24 or more projectors.

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