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Minolta RD-175
The Minolta RD-175 was an early digital SLR, introduced in 1995. Minolta combined an existing SLR with a three way splitter and three separate CCD image sensors, giving 1.75 megapixel (MP) resolution. The base of the DSLR was the Minolta Maxxum 500si Super (the Dynax 500si Super in Europe and as Alpha 303si Super in Asia). Agfa produced a version of the RD-175 retailed as the Agfa ActionCam. The RD-175 was also notable as the first consumer digital camera to be used professionally, being used to create the full-motion claymation adventure video game ''The Neverhood''. Technology Since state of the art CCD resolution at the time was not sufficient for Minolta, the light entering the central 12 mm × 16 mm area of the RD-175's focal plane was compressed by 0.4x relay optics behind the focal plane, similar to the optical reduction system used in the Nikon E series. The light bundled on the smaller sensor area increased the effective sensitivity (ISO) by stops. Then the light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SLR Camera
A single-lens reflex camera (SLR) is a camera that typically uses a mirror and prism system (hence "reflex" from the mirror's reflection) that permits the photographer to view through the lens and see exactly what will be captured. With twin lens reflex and rangefinder cameras, the viewed image could be significantly different from the final image. When the shutter button is pressed on most SLRs, the mirror flips out of the light path, allowing light to pass through to the light receptor and the image to be captured. History File:Hasselblad 1600F.jpg, Medium format SLR by Hasselblad (Model 1600F), Sweden File:Zenza BRONICA S2 with ZENZANON 100mm F2.8.JPG, Medium format SLR by Bronica (Model S2), Japan. Bronica's later model—the Bronica EC—was the first medium format SLR camera to use an electrically operated focal-plane shutter File:Asahiflex600.jpg, The 1952 (Pentax) Asahiflex, Japan's first single-lens reflex camera. File:Contaflex BW 2.JPG, The Contaflex III a single- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Film Speed
Film speed is the measure of a photographic film's sensitivity to light, determined by sensitometry and measured on various numerical scales, the most recent being the ISO system. A closely related ISO system is used to describe the relationship between exposure and output image lightness in digital cameras. Relatively insensitive film, with a correspondingly lower speed index, requires more exposure to light to produce the same image density as a more sensitive film, and is thus commonly termed a ''slow film''. Highly sensitive films are correspondingly termed ''fast films''. In both digital and film photography, the reduction of exposure corresponding to use of higher sensitivities generally leads to reduced image quality (via coarser film grain or higher image noise of other types). In short, the higher the sensitivity, the grainier the image will be. Ultimately sensitivity is limited by the quantum efficiency of the film or sensor. Film speed measurement systems His ... [...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] |
Minolta AF
The Minolta A-mount camera system was a line of photographic equipment from Minolta introduced in 1985 with the world's first integrated autofocus system in the camera body with interchangeable lenses. The system used a lens mount called A-mount, with a flange focal distance 44.50 mm, one millimeter longer, 43.5 mm, than the previous SR mount from 1958. The new mount was wider, 49.7 mm vs. 44.97 mm, than the older SR-mount and had a longer flange focal distance making old manual lenses incompatible with the new system. Minolta bought the autofocus technology of Leica Correfot camera which was partly used on the a-mount autofocus technology. The mount is now used by Sony, who bought the SLR camera division from Konica Minolta, Konica and Minolta having merged a few years before. The Minolta A-mount system was at first marketed as Maxxum in North America and α (Alpha) in Japan and the rest of Asia. In Europe, early Minolta A-mount cameras were initially ident ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hard Drive
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is accessed in a random-access manner, meaning that individual blocks of data can be stored and retrieved in any order. HDDs are a type of non-volatile storage, retaining stored data when powered off. Modern HDDs are typically in the form of a small rectangular box. Introduced by IBM in 1956, HDDs were the dominant secondary storage device for general-purpose computers beginning in the early 1960s. HDDs maintained this position into the modern era of servers and personal computers, though personal computing devices produced in large volume, like cell phones and tablets, rely on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PCMCIA
The Personal Computer Memory Card International Association (PCMCIA) was a group of computer hardware manufacturers, operating under that name from 1989 to 2009. Starting with the PCMCIA card in 1990 (the name later simplified to ''PC Card''), it created various standards for peripheral interfaces designed for laptop computers. History The PCMCIA (Personal Computer Memory Card International Association) industry organization was based on the original initiative of the British mathematician and computer scientist Ian H. S. Cullimore, one of the founders of the Sunnyvale-based Poqet Computer Corporation, who was seeking to integrate some kind of memory card technology as storage medium into their early DOS-based palmtop PCs, when traditional floppy drives and harddisks were found to be too power-hungry and large to fit into their battery-powered handheld devices. When in July 1989, Poqet contacted Fujitsu for their existing but still non-standardized SRAM memory cards, and Intel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interpolation
In the mathematical field of numerical analysis, interpolation is a type of estimation, a method of constructing (finding) new data points based on the range of a discrete set of known data points. In engineering and science, one often has a number of data points, obtained by sampling or experimentation, which represent the values of a function for a limited number of values of the independent variable. It is often required to interpolate; that is, estimate the value of that function for an intermediate value of the independent variable. A closely related problem is the approximation of a complicated function by a simple function. Suppose the formula for some given function is known, but too complicated to evaluate efficiently. A few data points from the original function can be interpolated to produce a simpler function which is still fairly close to the original. The resulting gain in simplicity may outweigh the loss from interpolation error and give better performance in ca ... [...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] |
F-number
In optics, the f-number of an optical system such as a camera lens is the ratio of the system's focal length to the diameter of the entrance pupil ("clear aperture").Smith, Warren ''Modern Optical Engineering'', 4th Ed., 2007 McGraw-Hill Professional, p. 183. It is also known as the focal ratio, f-ratio, or f-stop, and is very important in photography. It is a dimensionless number that is a quantitative measure of lens speed; increasing the f-number is referred to as ''stopping down''. The f-number is commonly indicated using a lower-case hooked f with the format ''N'', where ''N'' is the f-number. The f-number is the reciprocal of the relative aperture (the aperture diameter divided by focal length). Notation The f-number is given by: N = \frac \ where f is the focal length, and D is the diameter of the entrance pupil (''effective aperture''). It is customary to write f-numbers preceded by "", which forms a mathematical expression of the entrance pupil diameter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image Sensor Format
In digital photography, the image sensor format is the shape and size of the image sensor. The image sensor format of a digital camera determines the angle of view of a particular lens when used with a particular sensor. Because the image sensors in many digital cameras are smaller than the 24 mm × 36 mm image area of full-frame 35 mm cameras, a lens of a given focal length gives a narrower field of view in such cameras. Sensor size is often expressed as optical format in inches. Other measures are also used; see table of sensor formats and sizes below. Lenses produced for 35 mm film cameras may mount well on the digital bodies, but the larger image circle of the 35 mm system lens allows unwanted light into the camera body, and the smaller size of the image sensor compared to 35 mm film format results in cropping of the image. This latter effect is known as field-of-view crop. The format size ratio (relative to the 35 mm film format) is k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Single-lens Reflex Camera
A digital single-lens reflex camera (digital SLR or DSLR) is a digital camera that combines the optics and the mechanisms of a single-lens reflex camera with a digital imaging sensor. The reflex design scheme is the primary difference between a DSLR and other digital cameras. In the reflex design, light travels through the lens and then to a mirror that alternates to send the image to either a prism, which shows the image in the viewfinder, or the image sensor when the shutter release button is pressed. The viewfinder of a DSLR presents an image that will not differ substantially from what is captured by the camera's sensor as it presents it as a direct optical view through the main camera lens, rather than showing an image through a separate secondary lens. DSLRs largely replaced film-based SLRs during the 2000s. Major camera manufacturers began to transition their product lines away from DSLR cameras to mirrorless interchangeable-lens cameras (MILC) beginning in the 2010s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikon E Series
The Nikon E series, co-developed with Fujifilm, are autofocus 1.3 megapixel professional grade quasi- full frame (35mm) Nikon F-mount digital single lens reflex cameras (DSLR) manufactured by Nikon since 1995. The E series included the ''Nikon E2/E2S'', ''Nikon E2N/E2NS'' and the ''Nikon E3/E3S''. The S-variants are identical except they had triple the frame rate and a larger buffer. Its unique optical system bundles the light of the full-frame lenses to the small 2/3 inch CCD sensor. That gives approximately 4 stops more light at the small sensor, therefore delivering an exceptional (for that time) minimum sensitivity of 800 and maximum 3200 ISO, which remains usable for press and news use. Technology The Nikon E2/E2S and E2N/E2NS use a Nikon F4 subsystem, the E3/E3S uses a Nikon F100 subsystem. Optical system The E series uses a unique additional optical system that enables the small sensor to capture the field of view of a 35mm film, with a crop factor of 1. This c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
