Sigma Corporation is a Japanese company, manufacturing cameras, lenses, flashes and other photographic accessories. All Sigma products are produced in the company's own Aizu factory in Bandai, Fukushima, Japan. Although Sigma produces several camera models, the company is best known for producing high-quality lenses and other accessories that are compatible with the cameras produced by other companies.
The EF 50mm lenses are a group of normal prime lenses made by Canon that share the same focal length. These lenses are based on the classic double-Gauss lens, with the f/1.8 being a standard six-element double-Gauss with an air gap and powers between element 2 and 3 and its faster cousins adding additional elements. The 50mm focal length, when used with a 35mm film or full-frame sensor, has been widely considered to match the perspective seen by the human eye.
Tamron Co., Ltd. is a Japanese company manufacturing photographic lenses, optical components and commercial/industrial-use optics. Tamron Headquarters is located in Saitama City in the Saitama Prefecture of Japan.
The Pentax K-mount, sometimes referred to as the "PK-mount", is a bayonet lens mount standard for mounting interchangeable photographic lenses to 35 mm single-lens reflex (SLR) cameras. It was created by Pentax in 1975, and has since been used by all Pentax 35 mm and digital SLRs and also the MILC Pentax K-01. A number of other manufacturers have also produced many K-mount lenses and K-mount cameras.
The Canon EF-S 10–22mm f/3.5–4.5 USM lens is a wide to ultra-wide angle zoom lens for Canon digital single-lens reflex cameras with a Canon EF-S lens mount. The field of view has a 35 mm equivalent focal length of 16–35mm, which is analogous to the EF 16–35mm f/2.8L on a full-frame camera. The 10–22mm is an internal focusing lens. Of the 13 elements, one is of Canon's Super Ultra-Low Dispersion glass and three are aspherical elements.
Originally produced as Konica Minolta AF Zoom DT 18-200mm f/3.5-6.3 (D) by Konica Minolta in 2005, and currently produced by Sony, the Sony α DT 18-200mm f/3.5-6.3 (SAL-18200) is compatible with cameras using the Minolta A-mount and Sony A-mount lens mounts. The DT designation means this lens is designed to be used with a camera with an APS-C size sensor. When the 1.5× crop factor is considered, the lens has an effective equivalent 27–300mm focal length. The lens is derived from the Tamron AF 18-200mm f/3.5-6.3 XR Di II LD Aspherical [IF] (models A14M/A14S).
The Samyang 14mm f/2.8 ED AS IF UMC is Samyang's ultra wide angle prime lens for the 35 mm film format. It replaces the shortly sold Samyang 14mm f/2.8 IF ED MC Aspherical.
The SP AF 90mm f/2.8 Di 1:1 Macro lens is a macro lens produced by Tamron. It comes in the Canon EF-mount, Nikon F-mount, Pentax K-mount, and Sony A-mount. The lens was released in 1997. It received the European "Lens of the Year: 1997-1998" award. It was mechanically and cosmetically upgraded in February 2000. The lens is known for its high optical quality and reasonable price.
The Sigma 8–16mm lens is an enthusiast-level, ultra wide-angle rectilinear zoom lens made by Sigma Corporation specifically for use with APS-C small format digital SLRs. It is the first ultrawide rectilinear zoom lens with a minimum focal length of 8 mm, designed specifically for APS-C size image sensors. The lens was introduced at the February 2010 Photo Marketing Association International Convention and Trade Show. At its release it was the widest viewing angle focal length available commercially for APS-C cameras. It is part of Sigma's DC line of lenses, meaning it was designed to have an image circle tailored to work with APS-C format cameras. The lens has a constant length regardless of optical zoom and focus with inner lens tube elements responding to these parameters. The lens has hypersonic zoom autofocus.
Zoom creep is a phenomenon in zoom lenses where the angle of view of the lens changes when gravity is allowed to freely act on it. If the lens has a zoom ring, holding it when the lens is held upwards or downwards will prevent this change. In lenses with push-pull zoom, creep is prevented by holding the extending part of the lens. Some lenses, such as the Tamron SP AF 17-50mm f/2.8 XR Di II LD Aspherical [IF] and Canon EF-S 18-135mm f/3.5-5.6 IS STM, have a zoom lock to stop the effect.
The Pentax K-3 II is a flagship APS-C DSLR camera announced by Ricoh on April 22, 2015.
The Tamron 18-270mm F/3.5-6.3 Di II VC PZD is a superzoom lens for APS-C DSLR cameras, announced by Tamron on December 9, 2010. The Sony/Minolta A mount version is simply called Tamron 18-270mm F/3.5-6.3 Di II PZD as it lacks image stabilisation.
The Tamron SP 150-600mm F/5-6.3 Di VC USD is a super telezoom lens for DSLR cameras, announced by Tamron on November 7, 2013. The Sony A mount version is called Tamron SP 150-600mm F/5-6.3 Di USD as it lacks image stabilisation.
The Tamron AF 18-200mm F/3.5-6.3 XR Di II LD Aspherical [IF] Macro is a superzoom lens by Tamron, initially announced in 2005. A year later, Tamron announced the Tamron AF 18-250mm f/3.5-6.3 Di II LD Aspherical [IF] Macro with a slightly larger zoom range. However, in 2008, the 18-200 model was re-released with a built-in motor for Nikon bodies lacking a motor in the body - at that time the Nikon D40, D40x and D60.
The Tamron 28-300mm F/3.5-6.3 Di VC PZD is an interchangeable superzoom camera lens announced by Tamron on February 6, 2014.
The Tamron SP AF 60mm F/2 Di II LD IF Macro is an interchangeable macro lens designed for Canon, Nikon and Sony crop bodies and announced by Tamron on March 24, 2009. Among its peers, it stands out by its large aperture of f/2.
The Tamron AF 18-250mm F/3.5-6.3 Di II LD Aspherical (IF) Macro is an interchangeable superzoom lens by Tamron, designed for Canon, Nikon, Pentax and Sony APS-C bodies.
The Tamron 18-200mm F/3.5-6.3 Di III VC is an APS-C superzoom lens announced by Tamron on December 8, 2011. It can be mounted on Canon EOS-M and Sony E-mount (NEX) camera bodies.
