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Teleconverter
A teleconverter (sometimes called tele extender) is a secondary lens mounted between a camera and a photographic lens which enlarges the central part of an image obtained by the lens. For example, a 2× teleconverter for a 35 mm camera enlarges the central 12×18 mm part of an image to the size of 24×36 mm in the standard 35 mm film format. Teleconverters are typically made in 1.4×, 1.7×, 2× and 3× variants, with 1.4× and 2× being the most common. A 2× teleconverter doubles the apparent focal length of a given lens. Teleconverters also decrease the intensity of the light that reaches the film plane (or sensor) by the square of its magnification. A 2× teleconverter reduces the light to 1/4, doubles the focal ratio and halves the resolution of the master lens it is connected to. This, however, does not necessarily halve the resolution of the digital image. A closely related device reduces the focal length. It is generally marketed under the name speed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikon F-mount Teleconverter
The Nikon F-mount teleconverters are a group of magnifying lenses mounted between the lens and camera bodies using the Nikon F-mount. Currently, 1.4x, 1.7x and 2x converters are available separately; a fourth, the 1.25x, is available only with Nikon's newest 800mm supertelephoto lens. Function There are several generations, the newest are the E-II and the latest E-III series, which includes an aspherical lens. Teleconverters need a fast lens for fast, reliable autofocus. Depending on brightness, contrast and needed autofocus-speed, one should have a minimum total aperture between 11 and 5.6. A total aperture of 8 corresponds to a lens aperture of 5.6, 4 and 2.8 with a 1.4x, 2x and 3x teleconverter, respectively. Sometimes teleconverters do not convert aperture and focal length data included in the Exif information, even if the actual focus and exposure still will be correct. Not every teleconverter will support autofocus with every lens. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleconverter With Camera And Lens
A teleconverter (sometimes called tele extender) is a secondary lens mounted between a camera and a photographic lens which enlarges the central part of an image obtained by the lens. For example, a 2× teleconverter for a 35 mm camera enlarges the central 12×18 mm part of an image to the size of 24×36 mm in the standard 35 mm film format. Teleconverters are typically made in 1.4×, 1.7×, 2× and 3× variants, with 1.4× and 2× being the most common. A 2× teleconverter doubles the apparent focal length of a given lens. Teleconverters also decrease the intensity of the light that reaches the film plane (or sensor) by the square of its magnification. A 2× teleconverter reduces the light to 1/4, doubles the focal ratio and halves the resolution of the master lens it is connected to. This, however, does not necessarily halve the resolution of the digital image. A closely related device reduces the focal length. It is generally marketed under the name speed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleconverter
A teleconverter (sometimes called tele extender) is a secondary lens mounted between a camera and a photographic lens which enlarges the central part of an image obtained by the lens. For example, a 2× teleconverter for a 35 mm camera enlarges the central 12×18 mm part of an image to the size of 24×36 mm in the standard 35 mm film format. Teleconverters are typically made in 1.4×, 1.7×, 2× and 3× variants, with 1.4× and 2× being the most common. A 2× teleconverter doubles the apparent focal length of a given lens. Teleconverters also decrease the intensity of the light that reaches the film plane (or sensor) by the square of its magnification. A 2× teleconverter reduces the light to 1/4, doubles the focal ratio and halves the resolution of the master lens it is connected to. This, however, does not necessarily halve the resolution of the digital image. A closely related device reduces the focal length. It is generally marketed under the name speed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleside Converter
A teleside converter (also known as a telephoto conversion lens or a front mount teleconverter) is a secondary lens which is mounted on the front of a photographic lens to increase the effective focal length of the lens they are attached to. They are used on cameras and video cameras with non–interchangeable lenses to increase the magnification of the image. Their design is usually that of an afocal Galilean telescope that alters the width of the entering beam of light without affecting the divergence of the beam, so they can change the effective focal length 1 to 3 times without increasing focal ratio. The down side to teleside converters is they will vignette the image on the wide angle setting if used on a zoom lens. Minimum Focal Length without vignetting will increase inline with higher power of the teleside converter. Before vignetting appears (four black corners), light fall-off will appear first and in general shooting this light fall-off may not be noticeable. The other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canon Extender EF
The Canon Extender EF lenses are a group of teleconverter lenses made by Canon. These lenses are used between any compatible EF type lens and any of the Canon EOS line of cameras. When used with a compatible lens, they will multiply the focal length of the lens by a factor of either 1.4x or 2x, at the cost of decreasing the lens' aperture by 1 or 2 stops respectively. For example, using a 1.4x or 2x extender with the Canon EF 500mm f/4L IS USM would result in a 700mm f/5.6 or 1000mm f/8 lens. Overview Canon has released six models: * 1.4x (1988) * 1.4x II (2001) * 1.4x III (2010) * 2x (1987) * 2x II (2001) * 2x III (2010) Technical information The extenders are constructed with metal bayonets, and engineered plastic ends. There are no moving parts, other than the lens latch lock. Three generations of the extenders exist: the older 1.4× and 2×, the 1.4× II and 2× II, and the 1.4× III and 2.0× III. The II versions have weather-sealing and anti-reflective surfaces insi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barlow Lens
The Barlow lens, named after Peter Barlow, is a diverging lens which, used in series with other optics in an optical system, increases the effective focal length of an optical system as perceived by all components that are after it in the system. The practical result is that inserting a Barlow lens magnifies the image. A real barlow lens is not a single glass element, because that would generate chromatic aberration, and spherical aberration if the lens is not aspheric. More common configurations use three or more elements for achromatic correction or apochromatic correction and higher image quality. Telescope use In its astronomical use, a Barlow lens may be placed immediately before an eyepiece to effectively decrease the eyepiece's focal length by the amount of the Barlow's divergence. Since the magnification provided by a telescope and eyepiece is equal to the telescope's focal length divided by the eyepiece's focal length, this has the effect of increasing the magnificatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lens Mount
A lens mount is an interface – mechanical and often also electrical – between a photographic camera body and a lens. It is a feature of camera systems where the body allows interchangeable lenses, most usually the rangefinder camera, single lens reflex type, single lens mirrorless type or any movie camera of 16 mm or higher gauge. Lens mounts are also used to connect optical components in instrumentation that may not involve a camera, such as the modular components used in optical laboratory prototyping which join via C-mount or T-mount elements. Mount types A lens mount may be a screw-threaded type, a bayonet-type, or a breech-lock (friction lock) type. Modern still camera lens mounts are of the bayonet type, because the bayonet mechanism precisely aligns mechanical and electrical features between lens and body. Screw-threaded mounts are fragile and do not align the lens in a reliable rotational position, yet types such as the C-mount interface are still widely in us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convertible Lens
A camera lens (also known as photographic lens or photographic objective) is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically. There is no major difference in principle between a lens used for a still camera, a video camera, a telescope, a microscope, or other apparatus, but the details of design and construction are different. A lens might be permanently fixed to a camera, or it might be interchangeable with lenses of different focal lengths, apertures, and other properties. While in principle a simple convex lens will suffice, in practice a compound lens made up of a number of optical lens elements is required to correct (as much as possible) the many optical aberrations that arise. Some aberrations will be present in any lens system. It is the job of the lens designer to balance these and produce a design ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Lens
A camera lens (also known as photographic lens or photographic objective) is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically. There is no major difference in principle between a lens used for a still camera, a video camera, a telescope, a microscope, or other apparatus, but the details of design and construction are different. A lens might be permanently fixed to a camera, or it might be interchangeable with lenses of different focal lengths, apertures, and other properties. While in principle a simple convex lens will suffice, in practice a compound lens made up of a number of optical lens elements is required to correct (as much as possible) the many optical aberrations that arise. Some aberrations will be present in any lens system. It is the job of the lens designer to balance these and produce a desi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speed Booster
A telecompressor or focal reducer is an optical element used to reduce focal length, increase lens speed, and in some instances improve optical transfer function (OTF) performance. It is also widely known under the name “Speed Booster”, which is the commercial name of a line of telecompressors by the manufacturer Metabones. Popular applications include photography, videography, and astrophotography. In astrophotography, these qualities are most desirable when taking pictures of nearby large objects, such as nebulae. The effects and uses of the telecompressor are largely opposite to those of the teleconverter or Barlow lens. A combined system of a lens and a focal reducer has smaller Flange focal distance, back focus than the lens alone; this places restrictions on lenses and cameras that focal reducer might be used with. Lens adapters that include telecompressors are useful with digital MILC, mirrorless cameras. By combining a telecompressor within a lens adapter, mirrorless cam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecompressor
A telecompressor or focal reducer is an optical element used to reduce focal length, increase lens speed, and in some instances improve optical transfer function (OTF) performance. It is also widely known under the name “Speed Booster”, which is the commercial name of a line of telecompressors by the manufacturer Metabones. Popular applications include photography, videography, and astrophotography. In astrophotography, these qualities are most desirable when taking pictures of nearby large objects, such as nebulae. The effects and uses of the telecompressor are largely opposite to those of the teleconverter or Barlow lens. A combined system of a lens and a focal reducer has smaller back focus than the lens alone; this places restrictions on lenses and cameras that focal reducer might be used with. Lens adapters that include telecompressors are useful with digital mirrorless cameras. By combining a telecompressor within a lens adapter, mirrorless cameras can use the lenses of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z-mount
Nikon Z-mount (stylised as \mathbb) is an interchangeable lens mount developed by Nikon for its mirrorless digital cameras. In late 2018, Nikon released two cameras that use this mount, the full-frame Nikon Z 7 and Nikon Z 6. In late 2019 Nikon announced their first Z-mount camera with an APS-C sensor, the Nikon Z 50. In July 2020 the entry level full-frame Z 5 was introduced. In October 2020, Nikon announced the Nikon Z 6II and Nikon Z 7II, which succeed the Z 6 and Z 7, respectively. The APS-C lineup was expanded in July 2021, with the introduction of the retro styled Nikon Z fc, and in October 2021, Nikon unveiled the Nikon Z 9, which effectively succeeds the brand's flagship D6 DSLR. The APS-C lineup was further expanded with the Nikon Z 30, announced at the end of June 2022. Nikon SLR cameras, both film and digital, have used the Nikon F-mount with its 44 mm diameter since 1959. The Z-mount has a 55 mm diameter. The FTZ lens adapter allows many F-m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
