[ToC]

 

Ken Cameron, Sound and the Documentary Film, Sir Isaac Pitman & Sons, 1947

SHOWING HOW THE STRUCTURE OF THE IMAGE IS AFFECTED BY IMAGE CONTRACTION, IMAGE GROWTH, AND MUTUAL ACTION OF ADJACENT IMAGES

The effect is known as "slit-effect," "zero-shift," or, perhaps the best term, "image-spread." In the past it proved such a serious disadvantage to variable-area track work that considerable research was devoted to finding a solution. The use of ultra-violet light for exposing the film secured a marked improvement, but there still remained the problem of determining the processing conditions which would reduce the effect to negligible proportions.

Reference to Figs. 72-3 shows just how this effect arises.