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A combined pocket size Hyperscope & Psudoscope,
and more.

Discover the Eyebenda

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CYCLOPS - From Greek cyclos (KÚKÂOς), "circle" + ops, "eye"

"By removing stereo information with the Cyclopter we see paintings in enhanced depth, for visual evidence that they are flat is largely removed. This occurs simply by closing one eye. But keeping both open fools the brain into expecting stereo, so the effect of its loss is somewhat larger - as paintings jump off the canvas"

Professor Richard L. Gregory

(View the Cyclopter Gallery)

The Cyclops were mythical one-eyed giants of Homeric legend. Among other feats, they forged thunderbolts for Zeus. Their handiwork proved to be their own undoing, because Zeus is said to have used his thunderbolts to destroy them. In the middle of the 19th century Helmholtz used the term ‘cyclopean eye’ to allude to a hypothetical eye to explain identical binocular directions, combining both optical paths. About 100 years later in his ’Foundations of Cyclopean Perception’ Bela Julez used the same term to indicate ‘a central processing stage’ of vision.

In 1907 Carl Zeiss patented a prismatic device that combined both optical paths. Calling it a ‘Synopter’, he marketed it as a visual aid, in order that the gallery-visiting public could appreciate depth in paintings. Being relieved of binocular conflicts and vergence by which the visual system fixes a surface and computes distance, the viewer was able to pass more easily through the picture plane and into the virtual space of a painting. In addition, a viewing device that eliminated peripheral vision allowed the various depth cues in paintings using formal perspective* to assert themselves more powerfully. Viewing paintings with two eyes partially suppresses the operation of some of these cues, allowing them to retain a degree of attachment to the picture plane. Because their paintings used systems of perspective, works by Piero della Francesca, Bellini, Uccello, Velazquez, Rembrandt and many others, respond well to this form of viewing. It is important to remember, however, that artists did not make paintings to create an array of visual data merely to produce a photographic or an objective truth, but an artistic truth. Not all depth cues should therefore be accepted at their face value. A shadow, for example, may have been intended by the artist as a moral statement.

It is possible that some spectators will have noticed that they could achieve an effect similar to that experienced through the viewer simply by looking at paintings and photographs with one eye closed – although it seems generally agreed that the effect is less strong, and the space less tangible than when seen through the viewer. Any device that superimposes the two optical paths, because it reduces disparities to zero, is impossible to calibrate for strength of effect, as one may with enhancement factors for Hyperscopes or Pseudoscopes. Considering the widely differing reports by users of a Cyclopter, it might be a useful and interesting exercise to calibrate the observers, and discover what personal factors determine the contribution different individuals make.

It is difficult now to know either what level of commercial success Carl Zeiss had with his viewer, or what impact or relevance it may or may not have had upon the appreciation of painting at the time. But even while Zeiss was obtaining his patent in 1907, the world of art was leaving behind notions that had for centuries challenged it to produce paintings that were mimetic or copied the natural appearance of the world.

The Cubists’ revolutionary reorganisation of pictorial space denied the orthodoxy of  perspective that had formed a visual referential frame since the Early Renaissance, and instead asserted an independent ‘artistic’ space.
While it is interesting to examine paintings with the Cyclopter, it is also instructive to see what changes it makes to viewing the real world. It has sometimes been referred to as Brobdingnagian vision, meaning to make things look bigger, and some users consider this description justified.

What is striking is the overall flattening effect, and the ability to resolve features involving depth, which binocular discrepancies hide or confuse. This unfamiliar clarity can be quite engaging if you are looking at a scene with intermediate partially transparent screens, such as through a window covered with raindrops, and you will notice that the visual feedback about your relative motion is different from your normal perception of movement. Painters who are involved in the discipline of life-painting, or portraiture, may find the removal of binocular conflicts both interesting and useful. Due to the use of both eyes there is a persistent stereo latency – an expectation of stereoscopic experience, though none materializes.

The prismatic instrument by Carl Zeiss (diagram 1) used 5 hypotenuse prisms and one beamsplitting cube. It had a field of view of about 25º, and adaptations of it have been produced by various manufacturers for clinical applications, as well as microscopes and telescopes, for viewers who either need or prefer using both eyes. There is also a 4-mirror device, sometimes called an ’Orthoscope’ or ’Monoscope’ (diagram2) one of the mirrors being a beamsplitter, which also has a field of view limited to about 25º. The 2-mirror Cyclopter device shown below (diagram 3) has a field of view of about 30º, and allows far greater access to the cycloptic experience.

*Formal Perspective assumes a single vanishing point, and an eye that does not move. It is thought to have been invented by Brunelleschi in the early 15th Century and refined by others during the High Renaissance.

Cyclopter MK1 diagram 1
Cyclopter MK2 diagram 2
Diagram (1) - [ click to ENLARGE }
Diagram (2) - [ click to ENLARGE }
Cyclopter MK3 diagram 3
Diagram (3) - [ click to ENLARGE }