An autofocus (AF) optical system uses a sensor, a control system and a motor to focus on an automatically- or manually-selected point or area. An electronic rangefinder has a display instead of the motor; the adjustment of the optical system has to be done manually until indication. Autofocus methods are distinguished as active, passive or hybrid types.
A digital single-lens reflex camera is a digital camera that combines the optics and mechanisms of a single-lens reflex camera with a solid-state image sensor and digitally records the images from the sensor.
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 NikonD50 is a 6.1-megapixel entry-level digital single-lens reflex camera, sold from June 2005 until November 2006 by Nikon. It was Nikon's first DSLR aimed at the consumer market, and sold for US$899. It uses the Nikon F mount. The D50 is similar to the slightly older D70 using the same CCD sensor, with a slower maximum shutter speed and slightly smaller size; however, it continued to offer the internal focus motor of prior autofocus film and digital SLRs. Future entry-level Nikon DSLRs would eliminate the internal focus motor and require these motors to be in the lenses. Lack of a focus-motor in the camera eliminated the ability to autofocus with late film-era Nikkor AF and AF-D lenses, though these lenses work well on the D50.
Advanced Photo System type-C (APS-C) is an image sensor format approximately equivalent in size to the Advanced Photo System film negative in its C ("Classic") format, of 25.1×16.7 mm, an aspect ratio of 3:2 and Ø 30.15 mm field diameter. It is therefore also equivalent in size to the Super 35 motion picture film format, which has the dimensions of 24.89 mm × 18.66 mm and Ø 31.11 mm field diameter.
A full-frame DSLR is a digital single-lens reflex camera (DSLR) with a 35 mm image sensor format. Historically, 35 mm was one of the standard film formats, alongside larger ones, such as medium format and large format. The full-frame DSLR is in contrast to full-frame mirrorless interchangeable-lens cameras, and DSLR and mirrorless cameras with smaller sensors, much smaller than a full 35 mm frame. Many digital cameras, both compact and SLR models, use a smaller-than-35 mm frame as it is easier and cheaper to manufacture imaging sensors at a smaller size. Historically, the earliest digital SLR models, such as the Nikon NASA F4 or Kodak DCS 100, also used a smaller sensor.
The Pentax K10D and similar Samsung GX-10 are 10.2-megapixel digital single-lens reflex cameras launched in late 2006. They were developed in a collaboration between Pentax of Japan and Samsung of South Korea.
This article details lensesfor single-lens reflex and digital single-lens reflex cameras. The emphasis is on modern lenses for 35 mm film SLRs and for "full-frame" DSLRs with sensor sizes less than or equal to 35 mm.
The Pentax K20D and its clone, the Samsung GX-20, are 14.6 megapixel digital single-lens reflex cameras manufactured by Pentax that were announced on January 23, 2008. The K20D was available in the U.S. market from February 2008 through autumn 2009.
The Nikon D700 is a professional-grade full-frame digital single-lens reflex camera introduced by the Nikon Corporation in July 2008 and manufactured in Japan. It uses the same 12.1-megapixel "FX" CMOS image sensor as the Nikon D3, and is Nikon's second full-frame digital SLR camera.
This article discusses the cameras – mainly 35 mm SLRs – manufactured by Pentax Ricoh Imaging Corp. and its predecessors, Pentax Corporation and Asahi Optical Co., Ltd.. Pentax must not be confused with Pentax 6x7 or Pentax 67 which are 120 medium format 6x7cm film cameras.
Pentax lenses were first badged as Takumar. The Takumar branded lenses were well respected for their line of Super Takumar, which designated the high performance coating applied to the lens as well as the optical formulas used to make them. The majority of the industry at the time was still satisfied with the variations of the "plumb" coating process and later some of the two and three layer processes as well. Asahi Pentax soon introduced the Takumar Super-Multi-Coated line of lenses which was a 7 layer process as the industry had just caught up with similar forms of 5 layer multi-coated optics. Eventually Asahi Optical and Pentax slowly shifted much of their lens production under the Pentax name and transitioned some of the successful designs that were first introduced under the Takumar name to use Asahi/Pentax badging as well as beginning to use the "smc" abbreviation. Eventually the Asahi partnership disappeared and the Pentax name became solely used. Pentax lenses saw many feature changes to answer the market, such as: incorporating "Auto-Aperture" with the M42, the light weight and compactness with the 'M' series, Aperture Priority overrides with the 'A' series, and Auto-Focus with the 'F' series. Modern Pentax lenses for digital SLR cameras have seen the elimination of the aperture ring completely as found on Pentax DA and D-FA series lenses. They use the Pentax KAF mount. All of these lenses have an autofocus feature, either operated from the camera body or from an internal SDM motor. Pentax compatible lenses are also made by third-party companies.
The Canon EOS 500D is a 15-megapixel entry-level digital single-lens reflex camera, announced by Canon on 25 March 2009. It was released in May 2009. It is known as the EOS Kiss X3 in Japan, and as the EOS Rebel T1i in North America. It continues the Rebel line of mid-range DSLR cameras, is placed by Canon as the next model up from the EOS 450D, and has been superseded by the EOS 550D (T2i).
A mirrorless camera is a digital camera which, in contrast to DSLRs, does not use a mirror in order to ensure that the image presented to the photographer through the viewfinder is identical to that taken by the camera. They have come to replace DSLRs, which have historically dominated interchangeable lens cameras. Other terms include electronic viewfinder interchangeable lens (EVIL) cameras and compact system cameras (CSCs).
The Pentax K-5 is a 16.3-megapixel digital single-lens reflex camera, announced on September 20, 2010. It began shipping in mid-October 2010 and it was replaced by the Pentax K-5 II in the third quarter of 2012.
The Nikon 1 series is a discontinued camera line from Nikon, originally announced on 21 September 2011. The cameras utilized Nikon 1-mount lenses, and featured 1" CX format sensors.
Pentax K-01 is a mirrorless interchangeable-lens camera announced in February 2012. It uses the Pentax K mount.
The Nikon D3200 is a 24.2-megapixel DX format DSLR Nikon F-mount camera officially launched by Nikon on April 19, 2012. It is marketed as an entry-level DSLR camera for beginners and experienced DSLR hobbyists who are ready for more advanced specs and performance.
The Pentax K-30 is a 16.3-megapixel Pentax digital single-lens reflex camera, announced on 21 May 2012. At its introduction, it was in the middle of Pentax's DSLR range, above the now-discontinued entry-level K-r, and below the semi-pro K-5 and successor K-5 II.
The Pentax K-3 is a 24-megapixel Pentax high-end digital single-lens reflex camera with an APS-C sensor, announced on 7 October 2013. The Pentax K-3 is the successor to both the K-5 II and K-5 IIs models, which have a 16-megapixel sensor. The K-5 II had an optical low pass filter or anti-aliasing (AA) filter that can prevent the appearance of moire patterning on the captured image. This filter reduces the sharpness of the image, so Pentax also produced the K-5 IIs which omitted this filter. In the K-3, Pentax obviated the need for providing two separate models by including a selectable AA filter "simulator". This mechanism vibrates the sensor when switched on, slightly blurring the image in a way that replaces the function of the optical AA filter, providing the same benefit as the filter in the K-5 II and other cameras with an optical AA filter. When the AA simulator is disabled, the sensor records a sharper image, as in the K-5 IIs.
