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Pentax Q Series
The Pentax Q series is a series of mirrorless interchangeable-lens cameras made by Pentax and introduced in 2011 with the initial model Pentax Q. , it was the world's smallest, lightest interchangeable lens digital camera. The first models used a 1/2.3" (6.17 x 4.55 mm) back-illuminated sensor CMOS image sensor. The Q7, introduced in June 2013, uses a larger 1/1.7" type sensor (7.44 x 5.58 mm). The Q system is now discontinued. Characteristics The Pentax Q and Q10 sensors have a crop factor of 5.53× while the Pentax Q7 and Q-s1 have a crop factor of 4.65×. The original Pentax Q sensor has a 12.4 megapixels with 1.52 µm pixel pitch. All Pentax Q system cameras have a short flange focal distance (FFD) of 9.2mm. With a 5.53× crop factor, an adapted 100mm lens has the equivalent field of view (FOV) of a 553mm telephoto in the 35mm full-frame format. An additional implication of these relatively large crop factors is that depth of field (DOF) is proportionally increased ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mirrorless Interchangeable-lens Camera
A mirrorless camera is a photo camera featuring a single, removable lens and a digital display. The camera does not have a reflex mirror or optical viewfinder like a digital single-lens reflex (DSLR) camera, but may have an electronic viewfinder. Many mirrorless cameras retain a mechanical shutter. Like a DSLR, a mirrorless camera accepts any of a series of interchangeable lenses compatible with its lens mount. Terminology Mirrorless cameras are sometimes referred to as mirrorless interchangeable-lens cameras (MILC), or digital single-lens mirrorless (DSLM) cameras. This latter name highlights their connection to DSLRs. Other terms include electronic viewfinder interchangeable lens (EVIL) cameras and compact system cameras (CSCs). Overview Mirrorless cameras are mechanically simpler than DSLR cameras, and are smaller, lighter, and quieter due to the elimination of the moving mirror. While nearly all mirrorless cameras have a mechanical shutter, many also have an electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentax
is a brand name used primarily by the Japanese multinational imaging and electronics company Ricoh for DSLR cameras, lenses, sport optics (including binoculars and rifle scopes), and CCTV optics. The Pentax brand is also used by Hoya Corporation for medical products & services, TI Asahi for surveying instruments, and Seiko Optical Products for certain optical lenses. Corporate history Early history The company was founded as Asahi Kogaku Goshi Kaisha in November 1919 by Kumao Kajiwara, at a shop in the Toshima suburb of Tokyo, and began producing spectacle lenses (which it still manufactures). In 1938 it changed its name to , and by this time it was also manufacturing camera/cine lenses. In the lead-up to World War II, Asahi Optical devoted much of its time to fulfilling military contracts for optical instruments. At the end of the war, Asahi Optical was disbanded by the occupying powers, being allowed to re-form in 1948. The company resumed its pre-war activities, manufacturi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Back-illuminated Sensor
Comparison of simplified back-illuminated and front-illuminated pixel cross-sections A back-illuminated sensor, also known as backside illumination (BI) sensor, is a type of digital image sensor that uses a novel arrangement of the imaging elements to increase the amount of light captured and thereby improve low-light performance. The technique was used for some time in specialized roles like low-light security cameras and astronomy sensors, but was complex to build and required further refinement to become widely used. Sony was the first to reduce these problems and their costs sufficiently to introduce a 5-megapixel 1.75 µm BI CMOS sensor at general consumer prices in 2009.''Sony'', 2009 BI sensors from OmniVision Technologies have since been used in consumer electronics from other manufacturers as in the HTC EVO 4G Android smartphone, and as a major selling point for the camera in Apple's iPhone 4.''Apple'', 2010 Description A traditional, front-illuminated digital came ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CMOS
Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss", ) is a type of metal–oxide–semiconductor field-effect transistor (MOSFET) fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSFETs for logic functions. CMOS technology is used for constructing integrated circuit (IC) chips, including microprocessors, microcontrollers, memory chips (including CMOS BIOS), and other digital logic circuits. CMOS technology is also used for analog circuits such as image sensors (CMOS sensors), data converters, RF circuits (RF CMOS), and highly integrated transceivers for many types of communication. The CMOS process was originally conceived by Frank Wanlass at Fairchild Semiconductor and presented by Wanlass and Chih-Tang Sah at the International Solid-State Circuits Conference in 1963. Wanlass later filed US patent 3,356,858 for CMOS circuitry and it was granted in 1967. commercialized the technology with the trademark "COS-MO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image Sensor
An image sensor or imager is a sensor that detects and conveys information used to make an image. It does so by converting the variable attenuation of light waves (as they pass through or reflect off objects) into signals, small bursts of current that convey the information. The waves can be light or other electromagnetic radiation. Image sensors are used in electronic imaging devices of both analog and digital types, which include digital cameras, camera modules, camera phones, optical mouse devices, medical imaging equipment, night vision equipment such as thermal imaging devices, radar, sonar, and others. As technology changes, electronic and digital imaging tends to replace chemical and analog imaging. The two main types of electronic image sensors are the charge-coupled device (CCD) and the active-pixel sensor (CMOS sensor). Both CCD and CMOS sensors are based on metal–oxide–semiconductor (MOS) technology, with CCDs based on MOS capacitors and CMOS sensors based on M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crop Factor
In digital photography, the crop factor, format factor, or focal length multiplier of an image sensor format is the ratio of the dimensions of a camera's imaging area compared to a reference format; most often, this term is applied to digital cameras, relative to 35 mm film format as a reference. In the case of digital cameras, the imaging device would be a digital sensor. The most commonly used definition of crop factor is the ratio of a 35 mm frame's diagonal (43.3 mm) to the diagonal of the image sensor in question; that is, CF=diag35mm / diagsensor. Given the same 3:2 aspect ratio as 35mm's 36 mm × 24 mm area, this is equivalent to the ratio of heights or ratio of widths; the ratio of sensor areas is the square of the crop factor. The crop factor is sometimes used to compare the field of view and image quality of different cameras with the same lens. The crop factor is sometimes referred to as the focal length multiplier ("Film") since multiplying a le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flange Focal Distance
For an interchangeable lens camera, the flange focal distance (FFD) (also known as the flange-to-film distance, flange focal depth, flange back distance (FBD), flange focal length (FFL), back focus or register, depending on the usage and source) of a lens mount system is the distance from the mounting flange (the interlocking metal rings on the camera and the rear of the lens) to the film or image sensor plane. This value is different for different camera systems. The range of this distance, which will render an image clearly in focus within all focal lengths, is usually measured to a precision of hundredths of millimetres, and is not to be confused with depth of field. Lenses can be adapted from one mount (and respective FFD) to another. FFD determines whether infinity focus can be accomplished with a simple non-optical adapter. Optics to correct for distance introduce more cost and can lower image quality, so non-optical lens adapters are preferred. A simple non-optical ada ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field Of View
The field of view (FoV) is the extent of the observable world that is seen at any given moment. In the case of optical instruments or sensors it is a solid angle through which a detector is sensitive to electromagnetic radiation. Humans and animals In the context of human and primate vision, the term "field of view" is typically only used in the sense of a restriction to what is visible by external apparatus, like when wearing spectacles or virtual reality goggles. Note that eye movements are allowed in the definition but do not change the field of view when understood this way. If the analogy of the eye's retina working as a sensor is drawn upon, the corresponding concept in human (and much of animal vision) is the visual field. It is defined as "the number of degrees of visual angle during stable fixation of the eyes".Strasburger, Hans; Pöppel, Ernst (2002). Visual Field. In G. Adelman & B.H. Smith (Eds): ''Encyclopedia of Neuroscience''; 3rd edition, on CD-ROM. El ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depth Of Field
The depth of field (DOF) is the distance between the nearest and the furthest objects that are in acceptably sharp focus in an image captured with a camera. Factors affecting depth of field For cameras that can only focus on one object distance at a time, depth of field is the distance between the nearest and the farthest objects that are in acceptably sharp focus. "Acceptably sharp focus" is defined using a property called the "circle of confusion". The depth of field can be determined by focal length, distance to subject, the acceptable circle of confusion size, and aperture. Limitations of depth of field can sometimes be overcome with various techniques and equipment. The approximate depth of field can be given by: : \text \approx \frac for a given circle of confusion (c), focal length (f), f-number (N), and distance to subject (u). As distance or the size of the acceptable circle of confusion increases, the depth of field increases; however, increasing the size of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentax K-mount
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. Mounts The Pentax K-mount has undergone a number of evolutions over the years as new functionality has been added. In general, the term K-mount may refer to the original K-mount, or to all its variations. Originally designed by Zeiss for an alliance with Pentax, it was intended to be a common lens mount for a proposed series of cameras and lenses. However, the plan failed to work out and the two firms parted company amicably, but Pentax retained the lens mount and at least one Zeiss lens design for its own use. K-mount The original K-mount is a simple bayonet con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image Stabilization
Image stabilization (IS) is a family of techniques that reduce blurring associated with the motion of a camera or other imaging device during exposure. Generally, it compensates for pan and tilt (angular movement, equivalent to yaw and pitch) of the imaging device, though electronic image stabilization can also compensate for rotation. It is mainly used in high-end image-stabilized binoculars, still and video cameras, astronomical telescopes, and also smartphones. With still cameras, camera shake is a particular problem at slow shutter speeds or with long focal length lenses (telephoto or zoom). With video cameras, camera shake causes visible frame-to-frame jitter in the recorded video. In astronomy, the problem of lens shake is added to variation in the atmosphere, which changes the apparent positions of objects over time. Application in still photography In photography, image stabilization can facilitate shutter speeds 2 to 5.5 stops slower (exposures 4 to times l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shallow Focus
Shallow focus is a photographic and cinematographic technique incorporating a small depth of field. In shallow focus, one plane of the scene is in focus while the rest is out of focus. Shallow focus is typically used to emphasize one part of the image over another. Photographers sometimes refer to the aesthetic quality of the unfocused area(s) as bokeh. The opposite of shallow focus is deep focus, in which the entire image is in focus. Overview Shallow focus has become more popular in the 2000s and 2010s. It is also a means by which low budget filmmakers use to hide places that would require expensive props. It is often proclaimed by some to being a way to avoid the "video look." Extremely shallow focus – sometimes called ''bokeh porn'' – made its debut in cinematography in 2008 with the release of the Canon EOS 5D Mark II and the start of DSLR cinematography. Details The effect can be obtained by a larger aperture, a close viewpoint, a larger image sensor or a longer fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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