The Synoptic Art Experience

At the start of the 20th century, Moritz von Rohr invented the synopter: a device that removes 3D depth cues that arise from binocular disparities and vergence. In the absence of these visual cues, the observer is less aware of the physical flatness of the picture. This results in a surprisingly increased depth impression of pictorial space, historically known as the ‘plastic effect’. In this paper we present a practical design to produce a synopter and explore which elements of a painting influence the plastic effect. In the first experiment we showed 22 different paintings to a total of 35 observers, and found that they rate the synoptic effect rather consistent over the various paintings. Subsequent analyses indicated that at least three pictorial cues were relevant for the synoptic effect: figure–ground con­trast, compositional depth and shadows. In experiment 2, we used manipulated pictures where we tried to strengthen or weaken these cues. In all three cases we found at least one effect that confirmed our hypothesis. We also found substantial individual differences: some observers experience little effect, while others are very surprised by the effect. A stereo acuity test revealed that these differences could not be attributed to how well disparities are detected. Lastly, we informally tested our newly designed synopter in museums and found similar idiosyncratic appraisal. But the device also turned out to facilitate discussions among visitors.

20世纪初，Moritz von Rohr 发明了透视器：一种消除由双眼视差和聚合产生的三维深度线索的装置。在缺乏这些视觉线索的情况下，观察者对画面的物理平面性感知降低。这导致了对画面空间的深度印象出人意料地增强，历史上称之为‘塑料效果’。在本研究中，我们提出了一种实际设计的透视器，并探讨了绘画中的哪些元素会影响塑料效果。在第一项实验中，我们向35位观察者展示了22幅不同的画作，并发现他们在不同画作中对透视效果的评价相对一致。后续分析表明，至少有三个视觉线索与透视效果相关：图底对比、构图深度和阴影。在实验2中，我们使用了经过操控的图片，试图增强或减弱这些线索。在所有三种情况下，我们都至少发现了一个证实我们假设的效果。我们还发现了显著的个体差异：一些观察者对效果感知甚微，而另一些观察者则对效果感到非常惊讶。一项立体视力测试显示，这些差异不能归因于视差检测的准确性。最后，我们在博物馆非正式地测试了我们新设计的透视器，并发现了类似的个性评价。但该装置也证实了它能促进参观者之间的讨论。