The Moon Terminator Illusion, the Dolly Zoom Effect, and Moving vs Zooming
Popular YouTube personality Michael Stevens of VSauce posted this interesting 12-minute video yesterday explaining the optical science behind the “Moon Terminator Illusion” and the “Dolly Zoom Effect” (AKA the Hitchcock zoom).
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The Dolly Zoom Effect, popularized by Hitchcock in his films, keeps a subject at the same relative size in the frame while changing the distance and focal length — what results is a trippy effect that can add drama to a shot:
Stevens explains these two things and other optical phenomena in the video above. At about 7m20s in, Stevens talks about the difference between moving and zooming in on a scene and how the resulting photo/footage differs.
In case you’re interested, here’s a compilation video showing different uses of the Dolly Zoom Effect in film history: