Zograscope

Last updated August 23, 2023

A zograscope is an optical device for magnifying flat pictures that also has the property of enhancing the sense of the depth shown in the picture. It consists of a large magnifying lens through which the picture is viewed. Devices containing only the lens are sometimes referred to as graphoscopes. Other models have the lens mounted on a stand in front of an angled mirror. This allows someone to sit at a table and to look through the lens at the picture flat on the table. Pictures viewed in this way need to be left-right reversed; this is obvious in the case of writing. A print made for this purpose, typically with extensive graphical projection perspective, is called a vue d'optique or "perspective view".

History

In 1570, John Dee wrote A very fruitfull Preface ... specifying the chiefe Mathematicall Scieces, etc. in which he defined "zographie" as a mathematical art for representing visual images.^[3]^[4]
In 1677, German writer Johann Christoph Kohlhans described the effect of a convex lens in a camera obscura as if the subject appeared "naked before the eye in width, breadth, familiarity and distance".^[5]
In 1692, William Molyneux wrote in his Dioptrica Nova how "Pieces of Perspective appear Natural and strong through Convex Glasses duly apply'd".^[5]
Raree show boxes became very popular in the 17th century in The Netherlands.^[6] Some artists from the 17th-century Dutch Golden Age painting, like Pieter Janssens Elinga and Samuel Dirksz van Hoogstraten created a type of peep shows with an illusion of depth perception by manipulating the perspective of the view seen inside, usually the interior of a room. From around 1700 many of such "perspective boxes" or "optica" had a bi-convex lens with a large diameter and small dioptre for an exaggerated perspective, giving a stronger illusion of depth. Most pictures showed architectural and topographical subjects with linear perspectives.^[7]^[8]
In 1730, the first zograscopes, then called "optiques", were developed in Paris.^[3] Many perspective views, mainly of scenes from France and Germany but some from England, were published.^[9] Optiques incorporated a mirror but lacked any simple means of varying the distance of the lens from the image.^[3]
In 1745, the first English versions of the devices began to appear and soon many perspective views were printed for it, mostly of views with urban architecture.^[5] The oldest known reference to the English device is found in an advertisement in an English newspaper from April 1746.^[10] The term optical diagonal machine dates from as early as 1750.^[3]

Experience of zograscope viewing

Zograscopes created an unprecedentedly realistic experience of depicted scenes, so much so that Blake (2003) described it as "virtual reality".^[5] A zograscope allowed viewers to move their eyes over very large scenes, yielding an immersive experience.

Koenderink et al. (2013) showed that viewing photographs with a zograscope allowed observers to see depicted objects, such as Rodin's Danaid (Rodin), in objectively measured depth.^[11]

Explanation

Magnification of images was well understood by the time the first devices were constructed in the early 18th century. Basically, the image is placed at the focal point of a biconvex or plano-convex lens (a magnifying glass) allowing someone to view the magnified image at varying distances on the other side of the lens.^[11] Court and von Rorh (1935) suggested that the popularity of the early French models was because they allowed presbyopic purchasers to see the images clearly despite the French fashion against wearing glasses.^[9] But Chaldecott (1953) doubted this could have been the sole reason for the devices' enduring popularity, leaving the major factor to be the realistic appearance of the depicted images.^[3]

A zograscope makes a realistic experience for someone looking through it is by enhancing depth perception. One way is by minimizing other depth cues that specify the flatness and pictorial nature of the picture. The image is magnified, perhaps giving it a visual angle similar to the real scene the picture is depicting. The edges of the picture are blocked by the frame of the lens. The light coming from the lens to the eye is collimated, preventing accommodation. In early prints of interior scenes, some objects were hand-tinted with saturated colors whereas the background was tinted with "a pale wash"^[5] exploiting color contrast as a depth cue.^[12]

A second way a zograscope could enhance depth perception is by creating binocular stereopsis. Because each eye views the image from a different position, the surface of the picture could have binocular disparity from different magnification for the two eyes or from differences in the rotation of the images received by the eyes, so-called cyclodisparity.^[11] Such disparities create an overall slant of the picture surface around the vertical meridian ^[13] or horizontal meridian^[14] respectively. As well, coloured parts of the image will be refracted differently for each eye, creating a version of chromostereopsis. Even if the binocular disparity were incorrect for the surface of the image or any coloured parts of it, the stereoscopic information tends to integrate with the other depth information in the image.

Construction of modern variation

A simple zograscope can be built from a frame (by cutting a rectangular opening in the bottom of a cardboard box) and placing in the frame a large, magnifying, fresnel lens available from stationery stores. When this is placed over a computer monitor displaying a photograph of a natural scene, the depicted depth will be enhanced.

Related Research Articles

$<span class="mw-page-title-main">Lens</span> Optical device which transmits and refracts light$

A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (elements), usually arranged along a common axis. Lenses are made from materials such as glass or plastic and are ground, polished, or molded to the required shape. A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly focus or disperse waves and radiation other than visible light are also called "lenses", such as microwave lenses, electron lenses, acoustic lenses, or explosive lenses.

Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes when viewing distant objects. Most binoculars are sized to be held using both hands, although sizes vary widely from opera glasses to large pedestal-mounted military models.

In photography and cinematography, a normal lens is a lens that reproduces a field of view that appears "natural" to a human observer. In contrast, depth compression and expansion with shorter or longer focal lengths introduces noticeable, and sometimes disturbing, distortion.

In photography and cinematography, a wide-angle lens refers to a lens whose focal length is substantially smaller than the focal length of a normal lens for a given film plane. This type of lens allows more of the scene to be included in the photograph, which is useful in architectural, interior, and landscape photography where the photographer may not be able to move farther from the scene to photograph it.

Stereoscopy is a technique for creating or enhancing the illusion of depth in an image by means of stereopsis for binocular vision. The word stereoscopy derives from Greek στερεός (stereos) 'firm, solid', and σκοπέω (skopeō) 'to look, to see'. Any stereoscopic image is called a stereogram. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope.

Depth perception is the ability to perceive distance to objects in the world using the visual system and visual perception. It is a major factor in perceiving the world in three dimensions. Depth perception happens primarily due to stereopsis and accommodation of the eye.

A stereoscope is a device for viewing a stereoscopic pair of separate images, depicting left-eye and right-eye views of the same scene, as a single three-dimensional image.

An autostereogram is a two-dimensional (2D) image that can create the optical illusion of a three-dimensional (3D) scene. Autostereograms use only one image to accomplish the effect while normal stereograms require two. The 3D scene in an autostereogram is often unrecognizable until it is viewed properly, unlike typical stereograms. Viewing any kind of stereogram properly may cause the viewer to experience vergence-accommodation conflict.

A magnifying glass is a convex lens that is used to produce a magnified image of an object. The lens is usually mounted in a frame with a handle. A magnifying glass can be used to focus light, such as to concentrate the sun's radiation to create a hot spot at the focus for fire starting.

In film and photography, a prime lens is a fixed focal length photographic lens, typically with a maximum aperture from f2.8 to f1.2. The term can also mean the primary lens in a combination lens system. Confusion between these two meanings can occur without clarifying context. Alternate terms, such as primary focal length, fixed focal length, or FFL are sometimes used to avoid ambiguity.

A 3D display is a display device capable of conveying depth to the viewer. Many 3D displays are stereoscopic displays, which produce a basic 3D effect by means of stereopsis, but can cause eye strain and visual fatigue. Newer 3D displays such as holographic and light field displays produce a more realistic 3D effect by combining stereopsis and accurate focal length for the displayed content. Newer 3D displays in this manner cause less visual fatigue than classical stereoscopic displays.

<span class="mw-page-title-main">Pseudoscope</span> Binocular optical instrument that reverses depth perception

A pseudoscope is a binocular optical instrument that reverses depth perception. It is used to study human stereoscopic perception. Objects viewed through it appear inside out, for example: a box on a floor would appear as a box-shaped hole in the floor.

An optical instrument is a device that processes light waves, either to enhance an image for viewing or to analyze and determine their characteristic properties. Common examples include periscopes, microscopes, telescopes, and cameras.

A raree show, peep show or peep box is an exhibition of pictures or objects, viewed through a small hole or magnifying glass. In 17th and 18th century Europe, it was a popular form of entertainment provided by wandering showmen.

The megalethoscope is a larger version (mega-) of the alethoscope, which it largely superseded, and both are instruments for viewing single photographs with a lens to enlarge and to create some illusion of three-dimensionality. They were used to view photographic albumen prints that were coloured, perforated and mounted on a curved frame. Night effects were achieved when viewing pictures in transmitted light from a fitted oil or kerosine lamp and a daytime version of the same scene was seen when lit by the reflected light from two side mirrors. They are sophisticated versions of the peep show, and were designed by Carlo Ponti of Venice before 1862. Lke the similar graphoscope which descends from the eighteenth century zograscope predating photography, these devices were, and are, often confused with the stereoscope which was of a different design and effect. Improvements to the megalethoscope over the alethoscope, mainly the addition of a compound lens, are detailed in The Practical Mechanic's Journal of 1867.

Autostereoscopy is any method of displaying stereoscopic images without the use of special headgear, glasses, something that affects vision, or anything for eyes on the part of the viewer. Because headgear is not required, it is also called "glasses-free 3D" or "glassesless 3D". There are two broad approaches currently used to accommodate motion parallax and wider viewing angles: eye-tracking, and multiple views so that the display does not need to sense where the viewer's eyes are located. Examples of autostereoscopic displays technology include lenticular lens, parallax barrier, and may include Integral imaging, but notably do not include volumetric display or holographic displays.

Parallax scanning depth enhancing imaging methods rely on discrete parallax differences between depth planes in a scene. The differences are caused by a parallax scan. When properly balanced (tuned) and displayed, the discrete parallax differences are perceived by the brain as depth.

The globe effect, sometimes called the rolling ball effect or the spinning globe effect, is an optical phenomenon—perhaps partially an optical illusion—that occurs with visual optical instruments, in particular binoculars and telescopes, that are designed to be free of distortion. When these instruments are panned, the moving image appears to roll over a curved, convex surface. In 1949, Horst Koehler at Zeiss (Jena) suggested adding some pincushion distortion to the optical design to eliminate the globe effect. August Sonnefeld conducted experiments with volunteers, which supported the claim that a supplementary distortion could improve the imaging of visual optical instruments. Since that time, most binocular manufacturers have followed Zeiss's example and added pincushion distortion to their optical design.

Vue d'optique (French), vue perspective or perspective view refers to a genre of etching popular during the second half of the 18th century and into the 19th. Vues d'optique were specifically developed to provide the illusion of depth when viewed through a zograscope, also known as an "optical diagonal machine" or viewers with similar functions.

In Japanese art, a megane-e is a print designed using graphical perspective techniques and viewed through a convex lens to produce a three-dimensional effect. The term derives from the French vue d'optique. The device used to view them was called an Oranda megane or nozoki megane, and the pictures were also known as karakuri-e.

References

↑ Permutt, Cyril (1976). Collecting Old Cameras. New York: DaCapo Press. pp. 23, 27. ISBN 978-0-306-70855-8.
↑ Worldwidewords.org
1 2 3 4 5 Chaldecott, J.A. (1953). "The zograscope or optical diagonal machine". Annals of Science. 9 (4): 315–322. doi:10.1080/00033795300200243.
↑ Dee, J. (1570). [A very fruitfull Præface made by M. I. Dee, specifying the chiefe Mathematicall Sciẽces ...] In H. Billingsley, The elements of geometrie of the most auncient pholosopher Euclide of Megrara. London: John Daye. Retrieved from www.gutenberg.org
1 2 3 4 5 Blake, E. C. (2003). Zograscopes, virtual reality, and the mapping of polite society in eighteenth-century England. In L. Gitelman, & G. B. Pingree (Eds.), New Media, 1740-1915 (pp. 1-30). Cambridge, MA and London: MIT Press. Retrieved from https://mitpress-request.mit.edu/sites/default/files/titles/content/9780262572286_sch_0001.pdf
↑ "Peep-show box - Oxford Reference". oxfordreference.com.
↑ "Peepshow". visual-media.eu.
↑ Wagenaar; Duller; Wagenaar-Fischer. Dutch Perspectives.
1 2 Court, T. H., & von Rorh, M. (1935). On old instruments both for the accurate drawing and the correct viewing of perspectives. The Photographic Journal, 75(February), 54-66. Retrieved from https://archive.rps.org/archive/volume-75/734093?q=rohr%201935>
↑ Clayton, Tim (1997). The English Print 1688-1802. pp. 140–141.
1 2 3 Koenderink, Jan; Wijntjes, Maarten; Van Doorn, Andrea (2013). "Zograscopic Viewing". i-Perception. 4 (3): 192–206. doi:10.1068/i0585. PMC 3690410 . PMID 23799196.
↑ Troscianko, Tom; Montagnon, Rachel; Clerc, Jacques Le; Malbert, Emmanuelle; Chanteau, Pierre-Louis (1991). "The role of colour as a monocular depth cue". Vision Research. 31 (11): 1923–1929. doi:10.1016/0042-6989(91)90187-A. PMID 1771776.
↑ Ogle, K. N. (1950). Researchers in binocular vision. New York: Hafner Publishing Company.
↑ Blakemore, Colin; Fiorentini, Adriana; Maffei, Lamberto (1972). "A second neural mechanism of binocular depth discrimination". The Journal of Physiology. 226 (3): 725–749. doi:10.1113/jphysiol.1972.sp010006. PMC 1331173 . PMID 4564896.

External links

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[1] Permutt, Cyril (1976). Collecting Old Cameras. New York: DaCapo Press. pp. 23, 27. ISBN 978-0-306-70855-8.

[2] Worldwidewords.org

[Chaldecott1953-3] 1 2 3 4 5 Chaldecott, J.A. (1953). "The zograscope or optical diagonal machine". Annals of Science. 9 (4): 315–322. doi:10.1080/00033795300200243.

[4] Dee, J. (1570). [A very fruitfull Præface made by M. I. Dee, specifying the chiefe Mathematicall Sciẽces ...] In H. Billingsley, The elements of geometrie of the most auncient pholosopher Euclide of Megrara. London: John Daye. Retrieved from www.gutenberg.org

[NewMedia-5] 1 2 3 4 5 Blake, E. C. (2003). Zograscopes, virtual reality, and the mapping of polite society in eighteenth-century England. In L. Gitelman, & G. B. Pingree (Eds.), New Media, 1740-1915 (pp. 1-30). Cambridge, MA and London: MIT Press. Retrieved from https://mitpress-request.mit.edu/sites/default/files/titles/content/9780262572286_sch_0001.pdf

[6] "Peep-show box - Oxford Reference". oxfordreference.com.

[visualmedia-7] "Peepshow". visual-media.eu.

[8] Wagenaar; Duller; Wagenaar-Fischer. Dutch Perspectives.

[Court&1935-9] 1 2 Court, T. H., & von Rorh, M. (1935). On old instruments both for the accurate drawing and the correct viewing of perspectives. The Photographic Journal, 75(February), 54-66. Retrieved from https://archive.rps.org/archive/volume-75/734093?q=rohr%201935>

[10] Clayton, Tim (1997). The English Print 1688-1802. pp. 140–141.

[Koenderinket2013-11] 1 2 3 Koenderink, Jan; Wijntjes, Maarten; Van Doorn, Andrea (2013). "Zograscopic Viewing". i-Perception. 4 (3): 192–206. doi:10.1068/i0585. PMC 3690410 . PMID 23799196.

[Trosciankoet1991-12] Troscianko, Tom; Montagnon, Rachel; Clerc, Jacques Le; Malbert, Emmanuelle; Chanteau, Pierre-Louis (1991). "The role of colour as a monocular depth cue". Vision Research. 31 (11): 1923–1929. doi:10.1016/0042-6989(91)90187-A. PMID 1771776.

[13] Ogle, K. N. (1950). Researchers in binocular vision. New York: Hafner Publishing Company.

[14] Blakemore, Colin; Fiorentini, Adriana; Maffei, Lamberto (1972). "A second neural mechanism of binocular depth discrimination". The Journal of Physiology. 226 (3): 725–749. doi:10.1113/jphysiol.1972.sp010006. PMC 1331173 . PMID 4564896.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]