Variation and Likeness in Ambient Artistic Portraiture

Abstract

An artist-led exploration of portrait accuracy and likeness involved 12 Artists producing 12 portraits referencing a life-size 3D print of the same Sitter. The works were assessed during a public exhibition, and the resulting likeness assessments were compared to portrait accuracy as measured using geometric morphometrics (statistical shape analysis). Our results are that, independently of the assessors' prior familiarity with the Sitter's face, the likeness judgements tended to be higher for less morphologically accurate portraits. The two highest rated were the portrait that most exaggerated the Sitter's distinctive features, and a portrait that was a more accurate (but not the most accurate) depiction. In keeping with research showing photograph likeness assessments involve recognition, we found familiar assessors rated the two highest ranked portraits even higher than those with some or no familiarity. In contrast, those lacking prior familiarity with the Sitter's face showed greater favour for the portrait with the highest morphological accuracy, and therefore most likely engaged in face-matching with the exhibited 3D print. Furthermore, our research indicates that abstraction in portraiture may not enhance likeness, and we found that when our 12 highly diverse portraits were statistically averaged, this resulted in a portrait that is more morphologically accurate than any of the individual artworks comprising the average.

Likeness, Familiarity, and the Ambient Portrait Average

“…The tendency for the portrait averages to attract high likeness assessments may be due to the portrait averages being aesthetically pleasing. During the exhibition there were a few inquiries from the visitors (and two of the Artists) as to who created portraits K and W, and one visitor was overheard explaining the (manual) artistic techniques that were applied by the ‘artist’ to create the visual effects present in portrait average K. There is also the possibility that, as with our previous study (Hayes et al., 2018), the process of undertaking the assessments of the portraits likely provided otherwise unfamiliar visitors with a mental image of each Sitter’s face, and this priming effect has been found to increase recognisability (and therefore likeness) when unfamiliar viewers are exposed to a range of ambient photographs depicting a target face (e.g., Andrews, Jenkins, Cursiter, & Burton, 2015; Ritchie & Burton, 2017). As described in the Methods section, both portrait averages were exhibited last in each of the curated portrait sequences, and therefore, for those visitors who chose to assess each of the portraits following the exhibited sequence (and some were observed to do this), their assessment of the portrait average would likely have been influenced by their increased levels of familiarity.…”

“…The aims of this study were to see if ambient portrait averages were both shape accurate and good likenesses, and whether our 2017 findings (Hayes et al., 2018) would differ and/or be replicated with a more facially familiar Sitter (Mayor Bradbery) and a Sitter with relatively low levels of prior familiarity (Professor Wallace).…”

“…Because our previous study had found no significant impact of hue, medium, or scale on the likeness judgements of portraits (Hayes et al., 2018), the Artists completed their works using the materials, media, and dimensions of their choosing. The Artists had 4 weeks after the life sittings to complete and submit both portraits to RPAA on a set day to D. A., a member of the research team responsible for the collation of all Artist, portrait, and likeness assessment data, but not an Artist participant.…”

“…High resolution images of the portrait averages were achieved using the geometric morphometric thin plate spline (tps) software created by James Rohlf (2015). Digitising the x,y landmark coordinates ( tpsDig v232 ), checking the suitability of the overall variance ( tpsSmall v32 ) and creating the statistical average based on these landmark coordinates ( tpsSuper v32 ) are described in our 2017 study (Hayes et al., 2018), though for this iteration involved a larger, and different, suite of landmark coordinates were appled (Online Supplemental Material, Figures SM1 and SM2, Tables SM1 and SM2). Furthermore, the two Sitters’ image data sets required different landmark coordinates to adequately capture their depicted morphological variance.…”

“…During Australia’s 2017 National Science Week (12–19 August), we undertook a pilot study involving an exhibition of 12 portraits depicting the same Sitter which were assessed for likeness by 108 volunteers. The results were promising regarding the role of facial shape depiction, abstraction, and exaggeration in likeness assessments of portraits produced under relatively naturally occurring (ambient) conditions (Hayes et al., 2018). To assess the accuracy of the 12 portraits, we applied geometric morphometrics (statistical shape analysis), which resulted in the statistical average of the 12 portraits being the most accurate for depicting the Sitter’s facial shapes.…”