Angle-drawing accuracy as an objective performance-based measure of drawing expertise.

Abstract

Drawing expertise is obvious to the eye but the mechanisms underlying such expertise are less well known. An ecological drawing task was analyzed using a novel measure of success, degrees of error on selected angles in the image, which is an objective performance-based measure that was consistent with years of drawing experience. Thirty-three participants drew a complex three-dimensional (3D) still life by direct observation. The more experienced the participants, the more accurate they were at depicting angles in a still-life drawing. However, drawing experience made them no more accurate at verbal judgments of planar angles. This suggests that drawing expertise is consistent with actual accuracy in drawing angles—a domain-specific skill—but is not associated with more accurate overall angle judgment. Furthermore, drawing accuracy is not uniform across the image; it varies with angle size and context. Analysis of the interaction between expertise and angle size showed that the accuracy of experts was generally consistent, but less experienced drawers found some angles harder to draw than others. Finally, more experienced drawers were more accurate judging the slant of edges in the still life, suggesting that they may have a better understanding of the 3D properties of the subject.

Cain’s house task revisited and revived: Extending theory and methodology for quantifying drawing accuracy.

“…Domain general perceptual enhancement has also been shown in a recent study in which expert artists exhibited superior visual encoding both in rendering and nonrendering contexts (Glazek & Weisberg, 2010). The finding that angular perception correlates with drawing accuracy contrasts with the results of Carson and Allard's (2013) study, in which they reported no correlation between the estimation of planar and projected angles and drawing experience, despite revealing a relationship between perception of slanted angles and drawing experience. The angles used in the current study were most like the planar angles used in their study; however, we avoided using verbal report and instead asked participants to use a visual adjustment procedure with minimal motor demands.…”

The genesis of errors in drawing

“…Similarly, found that context-free angular reproduction accuracy correlated with the drawing accuracy. Drawing experience correlated with the accurate perception of those angles embedded in simple 2D geometric figures or within a complex still life (Carson & Allard, 2013;. This suggests that the relation between perceptual accuracy and drawing ability is not only determined by shape constancy mechanisms, but that reduced susceptibility to angular illusions in general could explain enhanced drawing ability.…”

Observational drawing biases are predicted by biases in perception: Empirical support of the misperception hypothesis of drawing accuracy with respect to two angle illusions

“…It remains unclear whether expertise in drawing is related to the degree of contextual biases in angle perception that are caused by task-irrelevant global properties of the object the angle is embedded (e.g., the degree to which individuals differ in their perceptual judgements of a 60°angle embedded in a cube versus a parallelogram or an isosceles versus a scalene triangle). Such information may further clarify why expert artists and nonartists differ in angle-drawing accuracy (Carson & Allard, 2013) and, more generally, identify the degree to which the transformational processes of visual input that determine our perceptual awareness of the environment can be inhibited.…”