The uncatchable smile in Leonardo da Vinci's La Bella Principessa Portrait

SORANZO, Alessandro and NEWBERRY, Michelle (2015). The uncatchable smile in Leonardo da Vinci's La Bella Principessa Portrait. Vision Research, 113 (Part A), 78-86.

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A portrait of uncertain origin recently came to light which, after extensive research and examination, was shown to be that rarest of things: a newly discovered Leonardo da Vinci painting entitled La Bella Principessa. This research presents a new illusion which is similar to that identified in the Mona Lisa; La Bella Principessa’s mouth appears to change slant depending on both the viewing distance and the level of blur applied to a digital version of the portrait. Through a series of psychophysics experiments, it was found that a perceived change in the slant of the La Bella Principessa's mouth influences her expression of contentment thus generating an illusion that we have coined the “uncatchable smile". The elusive quality of the Mona Lisa’s smile has been previously reported (Livingstone, 2000) and so the existence of a similar illusion in a portrait painted prior to the Mona Lisa becomes more interesting. The question remains whether Leonardo da Vinci intended this illusion. In any case, it can be argued that the ambiguity created adds to the portrait's allure.

Item Type: Article
Research Institute, Centre or Group - Does NOT include content added after October 2018: Psychology Research Group
Identification Number:
Page Range: 78-86
Depositing User: Alessandro Soranzo
Date Deposited: 03 Jun 2015 16:03
Last Modified: 18 Mar 2021 04:31

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