In photography, fish-eye lens is a wide-angle lens, in an image, a broad panoramic and hemispherical. Originally developed using weather [1] study cloud formation and so-called "all-sky lens," fish-eye lens quickly became popular in the general photography with its unique appearance, distorted. The photographers often use their vast landscapes to show the curve of the earth. Hemispherical photography is used for many scientific purposes the study plant canopy geometry, and calculate the near-ground solar radiation.
Fish-eye lens focal length depends on film format. For the popular 35 mm film format, typical focal length of the fish-eye lens is 8 mm and 10 mm image circle, 15-16 mm full-frame image. For digital cameras use a smaller electronic imaging, such as 1 / 4 "and 1 / 3" format CCD or CMOS sensor, the focal length of the "micro" fish-eye lens, can be as short as 1-2 mm.
All ultra-wide-angle lens with a certain amount of barrel distortion. While this can be easily corrected quite a wide viewing angle, ultra wide-angle lens with a straight angle greater than 90 degrees, it is difficult to design. Fisheye lenses achieve extremely wide viewing angle and a straight line image abstinence, choosing instead to a special mapping (for example: angle equisolid), which appeared in the typical convex to the image. Panoramic rotating lens or stitching images (cylindrical perspective) is not a fisheye photo.Directory[Hide]
A type of fish-eye lens
1.1 cycle
1.2 Full screen
1.3 small fish-eye lens
2 Focus
3 Other Uses
4 fish-eye lens to a 35mm camera
4.1 Circular Fisheye
4.2 full-screen fish-eye lens
5 mapping
6 See also
7 References
8 External links
[Edit] Types of fish-eye lens
In a circular fisheye image circle is written in the film or sensor area, the full-frame fisheye image circle is limited to film or sensor area.
In addition, different fisheye images distortions different, and how their distortion of the mapping function is called. A common type for consumer use perspective equisolid.[Edit] NoticeImages taken using a circular fish-eye lensImages taken with a circular fisheye.
The first type of fish-eye lens, to the development of "circular fish-eye" - a camera, took place in 180 ° hemisphere and projected this as a circle in the movie screen. Some fish-eye circles in orthographic projection model scientific applications. It has a 180 ° vertical viewing angle, horizontal and diagonal viewing angle is 180 °. Most circular fisheye lens covers a smaller image circle than the straight shot, so the angle of the frame will be completely dark.[Edit] full screen
Such as fisheye lenses gained popularity in general photography, camera companies began manufacturing the lens, fisheye image circle expanded to cover the entire 35mm film frame, which is a fish-eye type most frequently used photographers.
Angle of the image produced by these lenses only measures 180 degrees when measured from end to end: it has a 180 ° diagonal angle, and horizontal and vertical angle will be smaller, because a wide-angle equisolid mm fish optical head 15, the horizontal field of view is 147 °, the vertical FOV is 94 °. [2]
Full-frame fish-eye lens of the first mass-produced by the Nikon 16 mm lens in the early 1970s. Digital cameras and APS - C size sensor needs 10.5 mm lens to get the same effect as a 16mm lens on full frame sensor camera [3].
Because this type of digital technology, widely used, full-frame fish-eye effect can be the camera. The selected images can be digitally changed to become a full-frame fisheye images without the need for special lenses.
Bondi Beach, Sydney: a fish-eye lens of the camera-like results with Nikon D3100
15 mm fish-eye lens (type: equisolid angle), 35 mm film, to reduce the sliding frame
Nikkor 10.5 mm. A good example of a full-frame fish-eye lens used in a closed space
Fisheye Nikkor 10.5 mm (Type: equisolid angle), APS - C sized sensor, cropped to the rectangular
A full-frame lens, fish-eye lens 35mm camera.
A Peilun 8 mm f/3.5 lens.
[Edit] miniature fish-eye lens
Small fish-eye lens is designed for small-format CCD / CMOS imagers typically used in consumer cameras and security. [4] is a popular format, size 1 / 4 "(active area 3.6mmx2.7mm), 1 / 3" (active area 4.8mmx30.6 mm) and 1 / 2 "(6.6mmx4.8mm active area) according to active imaging area. the same lens, can form a circular image imager (such as 1 / 2 "), and the full-frame on the other (such as 1 / 4").[Edit] Focus
Sigma currently makes the 4.5 mm fish-eye lens to capture 180-degree view of the physical plant [5]. Sunex5.6 mm fisheye lens makes shooting 185-degree field of view 1.5 times 1.6 times round the Nikon and Canon SLR cameras.
Nikon produce 6 mm circular fisheye lens is originally designed for the Antarctic expedition. It features 220-degree field of vision to capture the entire sky and surrounding ground when pointed straight up. These lenses are no longer in production, Nikon, [6], is the use of interactive virtual reality images such as QuickTime VR and IPIX. As a wide field of view, very large, complex - Weight 5.2 kg (11 pounds), with a diameter of 236 mm (9.3 inches). It dwarfs a regular basis 35 mm SLR camera [7], has its own tripod mounting point, a feature usually present in large numbers, or telephoto lens focal length to reduce the tension, because the weight of the lens mount lenses than cameras.One pair for the 8mm fisheye lens, f/2.8 AIS Nikkor lens mounted on the Nikon F5 body.7.5 mm f/5.6 Fisheye-Nikkor installed in the body of the same year Nikon F.
8 mm fisheye lens, Nikon has made, it has been proven to be used for research purposes, because the equidistant projection (isometric), in which the distance along the radius of the image circle is proportional to the zenith.[Edit] Other usesPicture taken 16 mm full-frame lens fisheye, 35mm format digital SLR, the angle of the square before and after re-mapping tool with panoramic
With the right software, the image produced by the arc of fish-eye lens can be mapped to a traditional linear projection. Although this requires some loss of edge detail of the framework, this technique can produce images with a large field of view than the traditional linear lens. This is especially useful for creating panoramic images.
Some planetariums use a fisheye lens to project images in the form of two-dimensional film of the night sky into the interior of the dome. The Navitar's HemiStar6.75 mm fisheye for dome projection.
Flight simulator and combat simulator using visual effects, such as fish-eye lens Navitar's HemiStar, to create an immersive environment for pilots, air traffic control, or military training in.
Similarly, IMAX ball (formerly "Sky") movement, through the photographic image formats include a circular fish-eye lens, and through the same projection into a hemispherical screen.
Scientists and resource managers (for example, biologists, forestry, meteorology) using fisheye lens of hemispherical photography to calculate the index of plant canopy and near-ground solar radiation. Applications include assessment of forest health in winter king butterfly habitat characterization and management of vineyards.
Photographers and videographers use fisheye lens, so that they can get a camera action shots as close as possible, but also to capture aspects such as the skateboard set, players still retain the image.
Door peephole for a fisheye lens generally includes, providing a broad perspective. Security cameras often tend to have these lenses for the same reason.
In computer graphics, the circular fisheye images can be used to create environment maps the physical world. A complete 180-degree wide angle fish-eye images will apply to half-space mapping algorithm, if there is an appropriate application cubic meters. Environment map can be used to create 3D objects and virtual panoramic scenes.
[Edit] fish-eye lens to 35 mm camera[Edit] Circular Fisheye
Peleng 8 mm f/3.5 lens
Canon FD f/5.6 7.5 mm (note: not the EF mount) (not supplied)
Minolta ROKKOR -7.5 mm F4.0 Fisheye
Nikkor 8 mm F / 8 lens (not supplied)
7.5 mm f/5.6 Nikkor lens (not supplied)
A picture is taken from the entrance of the Louvre Museum 7.5 mm f/5.6 Fisheye-Nikkor lens
8 mm f/2.8 Nikkor lens (not supplied)
Nikkor 6 mm f/2.8 lens (not supplied)
Sigma EX DG8 mm f/3.5 lens (Sigma 8 mm instead of F / 4 EX DG)
Sigma 4.5 mm f/2.8 EX DC HSM lens circular fisheye APS - C sensor
Sunex [8] 185 degrees SuperFisheye [9] 5.6 毫米 f/5.6 SLR
Vemar12 mm f/5.6 fish eye / ultra-wide angle round the image full frame camera 135 if the points cover in place, 160 degree panorama. Usually as the installation of cameras in the range of T2, but no longer in production.
8-( 15 mm f/4L Canon EF lenses can be used either as a circular fisheye and full-frame fish-eye lens camera, 35mm full-frame)
[Edit] full-screen fish-eye lens
AF DX Fisheye 10.5mm f/2.8G-Nikkor ED (full frame on a DX sensor, nearly circular, the FX sensor is essential, if the hood is removed [10] - image circle slightly larger than the frame and There are some planting) at the top and bottom. [11]
MC Zenitar16 mm f/2.8 lens (model to choose from: MC Zenitar - K - Pentax Mount; MC Zenitar - M - M42 screwmount; MC Zenitar - H - Nikon mouth) [12]
Sigma EX DG15 mm f/2.8 diagonal fisheye lens [13]
Sigma 10 mm f/2.8 EX DC HSM lens fish-eye lens APS - C sensor.
Tokina 10-17 mm zoom lens f/3.5-4.5 fisheye APS - C sensor
Canon EF15 mm f/2.8 lens
Canon EF15 mm 8 - F / 4 USM zoom fisheye
Minolta / Sony AF16 mm f/2.8 fisheye lens
Olympus ZUIKO DIGITAL ED8 mm f/3.5 fisheye lens] of the Four Thirds camera [14]
Pentax DA 10 -17 mm f/3.5-4.5 Lens ED (IF) - full-frame image of APS - C sensor K-mount cameras
Sanyo optical 8 mm f/3.5 fisheye lens with CS APS - C sensor - Powell is also sold as, polar, Falcon, the same as the Vectra Rokinon 7mm and 6.5 mm lens Opteka. This manual focus lens, and report using three-dimensional projection [15] [16]
8-( 15 mm f/4L Canon EF lenses can be used either as a complete framework and a fish-eye fish-eye camera on the circle, 35mm full-frame, but only as a full-frame EOS Digital SLR cameras on the fish-eye head and APS - C / H size sensor)
[Edit] Function Mapping
Mapping the location of the object sideways displacement leading to the center of picture image. This conversion is a way of mapping function. From the center of the picture "R" is dependent on the focal length f of the optical system, and optical axis angle '? '.Illustration of the importance of the concept R, F, and variables? In the standard use of the mapping function.
The original channel was photographed, the camera's exterior wall to the left and center.
Gnomonical
Gnomonical, 40 ° right translation
Linear scale (equidistant)
Orthographic
The same area (corner equisolid)
Three-dimensional (FIT)
Ordinary (non-fisheye) lens:
Gnomonical or perspective: R = Ftan (?). Like a pinhole camera. Lines remain straight (distortion free). "T" must be less than 90 °. Gaged symmetrical with the optical axis and opening angle must be less than 180 °. Large opening angle is difficult to design and lead to higher prices.
Fish-eye lens can have many different mapping functions:
Linear scale (equidistant): R = F \ CDOT \ THETA Where? In radians. Practical point of measurement, for example, star maps. Panotools so use this type.
Orthography: R = FSIN (?). It looks like a ball and lying on the environment <maximum. 180 ° opening angle.
The same area (equisolid angle): R = 2fsin (? / 2). Each pixel subtends the same solid angle, or the same region-wide unit. It looks like a mirror ball, best special effects (high distance), for comparison area (cloud level determined). This type of popular, but it is the object of margin compression. The high price of the lens, but not extreme.
Three-dimensional (right): R = 2ftan (? / 2). The map is ideal for photographers, because it does not compress as much as the edge of the object. Sanyo is the only manufacturer not make such a fish-eye lens. These lenses can be based on different brandnames. Mapping software is easy to achieve.
Other mapping functions (such as adjustment of the lens distortion) [17] may also improve off-axis resolution fish-eye lens.
All types of fisheye lens bend straight lines. Opening angle 180 ° or more may be only a lot of barrel distortion.[Edit] See also
Map projection
[Edit] References
^ Hill, R. 1924. A camera shot of the entire sky. Royal Meteorological Society Quarterly 50:227-235.
^ The formula is \ {FOV text} = 4 \ CDOT \ arcsin \ left (\ frac {\ text box the size of the} {} {4 \ CDOT \ text {focus}} \ right) from the reverse mapping function; Dyxum , Gustavo Orensztajn
^ AF DX Fisheye-Nikkor 10.5 mm f/2.8G ED Lens Specifications
^ Miniature fish-eye lens
^ HTTP: / / www.sigma-photo.com/lenses/lenses_all_details.asp?id=3336&navigator=64.5 mm F2.8 EX DC HSM Fisheye notice
^ "Additional information 6 mm f/2.8 Fisheye-Nikkor lens." Malaysia network resources. Access 2008-11-11.
^ "Additional information 6 mm f/2.8 Fisheye-Nikkor lenses: 70 over." Malaysia network resources. Access 2008-11-11.
^ Sunex
^ SuperFisheye
^ [1]
^ AF DX Fisheye 10.5mm ED f/2.8G-Nikkor
^ MC Zenitar
^ Sigma EX DG15 mm f/2.8 diagonal fisheye
Olympus ZUIKO DIGITAL ED8 mm f/3.5 fisheye lens ^
^ "Sanyo 8 mm f/3.5 lens Aspherical IF MC Fish-eye." lenstip.com. Retrieved 14/08/2009.
^ Sanyo 8 mm f/3.5 fisheye lens CS
^ To adjust the lens distortion
[Edit] External links
Fish-eye image categories:
Fish-eye projection theory
Fisheye List
Glimpse of the fish-eye distortion effect
Fisheye camera
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