Rectilinear lens

In photography, a rectilinear lens is a photographic lens that yields images where straight features, such as the walls of buildings, appear with straight lines, as opposed to being curved. In other words, it is a lens with little or no barrel or pincushion distortion. At particularly wide angles, however, the rectilinear perspective will cause objects to appear increasingly stretched and enlarged as they near the edge of the frame. These types of lenses are often used to create forced perspective effects.

The most famous example is the Rapid Rectilinear Lens developed by John Henry Dallmeyer in 1866. It allowed distortionless photos to be taken quickly for the first time, and was a standard lens design for 60 years.[1]

The vast majority of video and still cameras use lenses that produce nearly rectilinear images. A popular alternative type of lens is a fisheye lens which produces a distinctly curvilinear, wide-angled result.

Panotools5618
Curvilinear (above) and rectilinear (below) image. Notice the barrel distortion typical for fisheye lenses in the curvilinear image. While this example has been rectilinear-corrected by software, high quality wide-angle lenses are built with optical rectilinear correction.

See also

References

  1. ^ Rudolf Kingslake (1989). A History of the Photographic Lens. Academic Press. pp. 59–. ISBN 978-0-12-408640-1.
Angle of view

In photography, angle of view (AOV) describes the angular extent of a given scene that is imaged by a camera. It is used interchangeably with the more general term field of view.

It is important to distinguish the angle of view from the angle of coverage, which describes the angle range that a lens can image. Typically the image circle produced by a lens is large enough to cover the film or sensor completely, possibly including some vignetting toward the edge. If the angle of coverage of the lens does not fill the sensor, the image circle will be visible, typically with strong vignetting toward the edge, and the effective angle of view will be limited to the angle of coverage.

A camera's angle of view depends not only on the lens, but also on the sensor. Digital sensors are usually smaller than 35mm film, and this causes the lens to have a narrower angle of view than with 35mm film, by a constant factor for each sensor (called the crop factor). In everyday digital cameras, the crop factor can range from around 1 (professional digital SLRs), to 1.6 (consumer SLR), to 2 (Micro Four Thirds ILC) to 4 (enthusiast compact cameras) to 6 (most compact cameras). So a standard 50mm lens for 35mm photography acts like a 50mm standard "film" lens on a professional digital SLR, but would act closer to an 80mm lens (1.6 x 50mm) on many mid-market DSLRs, and the 40 degree angle of view of a standard 50mm lens on a film camera is equivalent to a 28 - 35mm lens on many digital SLRs.

Canon EF 11–24mm lens

The EF 11–24 mm lens is a professional wide-angle lens made by Canon Inc. It was announced on February 5, 2015, and at that time was the widest rectilinear lens ever made for the 35 mm format in either its film or digital versions.The lens has an EF mount to work with the EOS line of cameras. Other than the front element, it is sealed against dust and water, and features a diaphragm which remains nearly circular. It produces minimally distorted images.

Cosina

Cosina Co., Ltd. (株式会社コシナ, Kabushiki-gaisha Koshina) is a manufacturer of high-end optical glass, optical precision equipment, cameras, video and electronic related equipment, based in Nakano, Nagano Prefecture, Japan.

Distortion (optics)

In geometric optics, distortion is a deviation from rectilinear projection; a projection in which straight lines in a scene remain straight in an image. It is a form of optical aberration.

Edward Weston

Edward Henry Weston (March 24, 1886 – January 1, 1958) was a 20th-century American photographer. He has been called "one of the most innovative and influential American photographers…" and "one of the masters of 20th century photography." Over the course of his 40-year career Weston photographed an increasingly expansive set of subjects, including landscapes, still lives, nudes, portraits, genre scenes and even whimsical parodies. It is said that he developed a "quintessentially American, and specially Californian, approach to modern photography" because of his focus on the people and places of the American West. In 1937 Weston was the first photographer to receive a Guggenheim Fellowship, and over the next two years he produced nearly 1,400 negatives using his 8 × 10 view camera. Some of his most famous photographs were taken of the trees and rocks at Point Lobos, California, near where he lived for many years.

Weston was born in Chicago and moved to California when he was 21. He knew he wanted to be a photographer from an early age, and initially his work was typical of the soft focus pictorialism that was popular at the time. Within a few years, however, he abandoned that style and went on to be one of the foremost champions of highly detailed photographic images.

In 1947 he was diagnosed with Parkinson's disease and he stopped photographing soon thereafter. He spent the remaining ten years of his life overseeing the printing of more than 1,000 of his most famous images.

Eugène Atget

Eugène Atget (French: [adʒɛ]; 12 February 1857 – 4 August 1927) was a French flâneur and a pioneer of documentary photography, noted for his determination to document all of the architecture and street scenes of Paris before their disappearance to modernization. Most of his photographs were first published by Berenice Abbott after his death. An inspiration for the surrealists and other artists, his genius was only recognized by a handful of young artists in the last two years of his life, and he did not live to see the wide acclaim his work would eventually receive.

Fisheye lens

A fisheye lens is an ultra wide-angle lens that produces strong visual distortion intended to create a wide panoramic or hemispherical image. Fisheye lenses achieve extremely wide angles of view. Instead of producing images with straight lines of perspective (rectilinear images), fisheye lenses use a special mapping (for example: equisolid angle), which gives images a characteristic convex non-rectilinear appearance.

The term fisheye was coined in 1906 by American physicist and inventor Robert W. Wood based on how a fish would see an ultrawide hemispherical view from beneath the water (a phenomenon known as Snell's window). Their first practical use was in the 1920s for use in meteorology to study cloud formation giving them the name "whole-sky lenses". The angle of view of a fisheye lens is usually between 100 and 180 degrees while the focal lengths depend on the film format they are designed for.

Mass-produced fisheye lenses for photography first appeared in the early 1960s and are generally used for their unique, distorted appearance. For the popular 35 mm film format, typical focal lengths of fisheye lenses are between 8 mm and 10 mm for circular images, and 15–16 mm for full-frame images. For digital cameras using smaller electronic imagers such as ​1⁄4" and ​1⁄3" format CCD or CMOS sensors, the focal length of "miniature" fisheye lenses can be as short as 1 to 2 mm.

These types of lenses also have other applications such as re-projecting images that were originally filmed through a fisheye lens, or created via computer generated graphics, onto hemispherical screens. Fisheye lenses are also used for scientific photography such as recording of aurora and meteors, and to study plant canopy geometry and to calculate near-ground solar radiation. They are perhaps most commonly encountered as peephole door viewers to give the user a wide field of view.

Focal length

The focal length of an optical system is a measure of how strongly the system converges or diverges light. For an optical system in air, it is the distance over which initially collimated (parallel) rays are brought to a focus. A system with a shorter focal length has greater optical power than one with a long focal length; that is, it bends the rays more sharply, bringing them to a focus in a shorter distance.

In most photography and all telescopy, where the subject is essentially infinitely far away, longer focal length (lower optical power) leads to higher magnification and a narrower angle of view; conversely, shorter focal length or higher optical power is associated with lower magnification and a wider angle of view. On the other hand, in applications such as microscopy in which magnification is achieved by bringing the object close to the lens, a shorter focal length (higher optical power) leads to higher magnification because the subject can be brought closer to the center of projection.

H. C. Casserley

Henry Cyril Casserley (12 June 1903 – 16 December 1991) was a British photographer of steam railways. His prolific work in the 1920s and 1930s, the result of travelling to remote corners of the railway network in the United Kingdom and Ireland, has provided subsequent generations with a valuable source of illustrations for books and magazines.

Index of physics articles (R)

The index of physics articles is split into multiple pages due to its size.

To navigate by individual letter use the table of contents below.

Nautilus (photograph)

Nautilus is a black-and-white photograph taken by Edward Weston in 1927 of a single nautilus shell standing on its end against a dark background. It has been called "one of the most famous photographs ever made" and "a benchmark of modernism in the history of photography."

Nikkor 13mm f/5.6

The Nikkor 13mm f/5.6 is an ultra-wide angle rectilinear lens which was manufactured by Nikon for use on Nikon 135 film format SLR cameras until 1998, at which time it was discontinued. It has been dubbed 'The Holy Grail', for its low-distortion ultra-wide capabilities. The lens was produced by Nikon only upon receipt of an order, thus making it one of the Nikon lenses with the least number manufactured.

Nikon F2

The Nikon F2 is a professional level, interchangeable lens, 35 mm film, single-lens reflex (SLR) camera. It was manufactured by the Japanese optics company Nippon Kogaku K. K. (Nikon Corporation since 1988) in Japan from September 1971 to 1980. It used a horizontal-travel focal plane shutter with titanium shutter curtains and a speed range of 1 to 1/2000 second (up to 10 seconds using the self-timer) plus Bulb and Time, and flash X-sync of 1/80th second. It had dimensions (with DE-1 head, see below) of 98 mm height, 152.5 mm width, 65 mm depth and 730 g weight. It was available in two colors: black with chrome trim and all black.

The F2 is the second member of the long line of Nikon F-series professional level 35 mm SLRs that began with the Nikon F (manufactured 1959–1974) and followed each other in a sort of dynastic succession as the top-of-the-line Nikon camera. The other members were the F3 (1980–2001), F4 (1988–1996), F5 (1996–2005) and F6 (2004–present). The F-series do not share any major components except for the all-important bayonet lens mount ('F mount').

All Nikon professional F-series SLRs are full system cameras. This means that each camera body serves as only a modular hub.

Normal lens

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

Rangefinder camera

A rangefinder camera is a camera fitted with a rangefinder, typically a split-image rangefinder: a range-finding focusing mechanism allowing the photographer to measure the subject distance and take photographs that are in sharp focus. Most varieties of rangefinder show two images of the same subject, one of which moves when a calibrated wheel is turned; when the two images coincide and fuse into one, the distance can be read off the wheel. Older, non-coupled rangefinder cameras display the focusing distance and require the photographer to transfer the value to the lens focus ring; cameras without built-in rangefinders could have an external rangefinder fitted into the accessory shoe. Earlier cameras of this type had separate viewfinder and rangefinder windows; later the rangefinder was incorporated into the viewfinder. More modern designs have rangefinders coupled to the focusing mechanism, so that the lens is focused correctly when the rangefinder images fuse; compare with the focusing screen in non-autofocus SLRs.

Almost all digital cameras, and most later film cameras, measure distance using electroacoustic or electronic means and focus automatically (autofocus); however, it is not customary to speak of this functionality as a rangefinder.

Rapid Rectilinear

The Rapid Rectilinear also named Aplanat is a famous photographic lens design.

The Rapid Rectilinear is a lens that is symmetrical about its aperture stop with four elements in two groups. It was introduced by John Henry Dallmeyer in 1866. The symmetry of the design greatly reduces radial distortion.

Rectilinear

Rectilinear means related to a straight line; it may refer to:

Rectilinear grid, a tessellation of the Euclidean plane

Rectilinear lens, a photographic lens

Rectilinear locomotion, a form of animal locomotion

Rectilinear polygon, a polygon whose edges meet at right angles

Rectilinear propagation, a property of waves

Rectilinear Research Corporation, a now defunct manufacturer of high-end loudspeakers

Rectilinear style, the third historical division of English Gothic architecture

Rectilinear motion or linear motion is motion along a straight line

Sigma 12–24mm f/4.5–5.6 lens

The Sigma 12-24mm f/4.5-5.6 EX DG HSM is a professional-level wide-angle zoom lens made by Sigma Corporation. It was once the widest rectilinear lens available (with this distinction has since been taken over by Canon EF 11-24mm f/4L) for full-frame 35mm SLR cameras, providing a field of view of 122 degrees. It is still the widest full-frame rectilinear lens available for Nikon as of 2016. This distinction has been taken over by the Irix 11mm f/4 lens released in 2017. However, the Sigma lens still remain the widest autofocus full-frame zoom lens available for Nikon camera as the Irix lens is a manual focus prime lens. Other lenses available with focal lengths of 12mm or less are either incompatible with full-frame cameras or are intentionally distorted. The Sigma 12-24 has low distortion even compared to less wide zooms like the Canon EF 16-35mm lens.This lens is available in Canon, Nikon, and Sigma, Pentax, and Sony mounts. HSM focusing is available only in the Canon, Nikon, and Sigma variants. The build quality is typical of Sigma EX lenses, with a painted metal lens barrel and damped focus and zoom rings. As expected for a lens of these specifications, there is a large protruding front element.

Ultra wide angle lens

An ultra wide-angle lens is a lens whose focal length is shorter than the short side of film or sensor.Thus the term denotes a different range of lenses, relative to the size of the sensor in the camera in question.

For 1" any 9mm or shorter is considered ultra wide angle.For 4/3" any 12mm or shorter lens is ultra wide angle.For APS-C any lens shorter than 15 mm.

For 35mm film or full-frame sensor any lens shorter than 24 mm

For 6x4.5 cm any lens shorter than 41 mm

For 6x6 cm and 6x7 cm any lens shorter than 56 mm

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.