Tuesday, 3 January 2017

persistence of vision

Previously we learnt that the comprehensive picture that we hold in our heads of the world around us is fragmentary and somewhat of a figment of our imaginations, but we didn’t have the vocabulary and the stage-directions to really frame this phenomena of inattention until coming upon this interesting article from Æon magazine on how film makers and special-effects artists (knowingly or otherwise) take advantage of the gaps in our perception to enthrall audiences and blind us to other continuity errors.
Saccades and saccadic masking describe the mechanisms that cause the eyes to dart around and follow motion and gather information on what’s changing and emergent—rather than what’s stationary and constant and therefore acceptable to be ignored. Without this ability to focus selectively and reconstruct the peripheral environment from memory and recycled footage, our heads would be clogged not with smooth and sharp transitions but rather blurred and smeared images. We’re only able to resolve, on the fly, three or four elements of a scene. “Smooth pursuits” are also possible in reading or tracing out a visual target, but it’s rarer that as observers we aren’t playing catch-up and are mentally re-building the setting and sequence despite the on-screen polish and our memories of the experience, both cinematic and authentic.