The Leica M8 is the first digital camera in the rangefinder M series introduced by Leica Camera AG on 14 September 2006. It uses an APS-H 10.3-megapixel CCD image sensor designed and manufactured by Kodak .
74-427: As of 15 November 2014, the most recent firmware version is 2.024. The M8 body is slightly thicker than the classic MP and M7 (approximately ~14% thicker). It is an all-metal body made of a high-strength magnesium alloy. The top and base plates are cut from brass billets, before receiving a black or silver chrome finish. The M8 supports all existing Leica M-mount lenses; however, some older models might not offer all
148-423: A charge amplifier , which converts the charge into a voltage . By repeating this process, the controlling circuit converts the entire contents of the array in the semiconductor to a sequence of voltages. In a digital device, these voltages are then sampled, digitized, and usually stored in memory; in an analog device (such as an analog video camera), they are processed into a continuous analog signal (e.g. by feeding
222-481: A shift register . The essence of the design was the ability to transfer charge along the surface of a semiconductor from one storage capacitor to the next. The concept was similar in principle to the bucket-brigade device (BBD), which was developed at Philips Research Labs during the late 1960s. The first experimental device demonstrating the principle was a row of closely spaced metal squares on an oxidized silicon surface electrically accessed by wire bonds. It
296-416: A 1.33 crop factor . It is calibrated for an ISO sensitivity range of 160–2500. The sensor includes indium tin oxide as a constituent material, which Kodak claims leads to low noise, high sensitivity, and wide dynamic range . It is designed for use with lenses with short back focal lengths – such as those common to rangefinder cameras – by including a microlens array to reduce fall off in intensity from
370-485: A CCD is the higher cost: the cell area is basically doubled, and more complex control electronics are needed. An intensified charge-coupled device (ICCD) is a CCD that is optically connected to an image intensifier that is mounted in front of the CCD. An image intensifier includes three functional elements: a photocathode , a micro-channel plate (MCP) and a phosphor screen. These three elements are mounted one close behind
444-669: A cooling system—using either thermoelectric cooling or liquid nitrogen—to cool the chip down to temperatures in the range of −65 to −95 °C (−85 to −139 °F). This cooling system adds additional costs to the EMCCD imaging system and may yield condensation problems in the application. However, high-end EMCCD cameras are equipped with a permanent hermetic vacuum system confining the chip to avoid condensation issues. The low-light capabilities of EMCCDs find use in astronomy and biomedical research, among other fields. In particular, their low noise at high readout speeds makes them very useful for
518-428: A factor of 2–3 compared to the surface-channel CCD. The gate oxide, i.e. the capacitor dielectric , is grown on top of the epitaxial layer and substrate. Later in the process, polysilicon gates are deposited by chemical vapor deposition , patterned with photolithography , and etched in such a way that the separately phased gates lie perpendicular to the channels. The channels are further defined by utilization of
592-555: A few percent. That image can then be read out slowly from the storage region while a new image is integrating or exposing in the active area. Frame-transfer devices typically do not require a mechanical shutter and were a common architecture for early solid-state broadcast cameras. The downside to the frame-transfer architecture is that it requires twice the silicon real estate of an equivalent full-frame device; hence, it costs roughly twice as much. The interline architecture extends this concept one step further and masks every other column of
666-429: A full-frame device, all of the image area is active, and there is no electronic shutter. A mechanical shutter must be added to this type of sensor or the image smears as the device is clocked or read out. With a frame-transfer CCD, half of the silicon area is covered by an opaque mask (typically aluminum). The image can be quickly transferred from the image area to the opaque area or storage region with acceptable smear of
740-592: A gain register is placed between the shift register and the output amplifier. The gain register is split up into a large number of stages. In each stage, the electrons are multiplied by impact ionization in a similar way to an avalanche diode . The gain probability at every stage of the register is small ( P < 2%), but as the number of elements is large (N > 500), the overall gain can be very high ( g = ( 1 + P ) N {\displaystyle g=(1+P)^{N}} ), with single input electrons giving many thousands of output electrons. Reading
814-401: A large lateral electric field from one gate to the next. This provides an additional driving force to aid in transfer of the charge packets. The CCD image sensors can be implemented in several different architectures. The most common are full-frame, frame-transfer, and interline. The distinguishing characteristic of each of these architectures is their approach to the problem of shuttering. In
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#1732787224027888-406: A niche of photographers who use photographic filters that block the visible spectrum of light to do infrared photography. Leica announced a perpetual upgrade program on 31 January 2008. To keep a user's M8 up to date with newer releases, owners can send their M8 to Leica for upgrades. The first upgrade offered under this program is an improved shutter designed for quieter operation, at the cost of
962-399: A non-equilibrium state called deep depletion. Then, when electron–hole pairs are generated in the depletion region, they are separated by the electric field, the electrons move toward the surface, and the holes move toward the substrate. Four pair-generation processes can be identified: The last three processes are known as dark-current generation, and add noise to the image; they can limit
1036-417: A p+ doped region underlying them, providing a further barrier to the electrons in the charge packets (this discussion of the physics of CCD devices assumes an electron transfer device, though hole transfer is possible). The clocking of the gates, alternately high and low, will forward and reverse bias the diode that is provided by the buried channel (n-doped) and the epitaxial layer (p-doped). This will cause
1110-409: A reflective material such as aluminium. When the exposure time is up, the cells are transferred very rapidly to the hidden area. Here, safe from any incoming light, cells can be read out at any speed one deems necessary to correctly measure the cells' charge. At the same time, the exposed part of the CCD is collecting light again, so no delay occurs between successive exposures. The disadvantage of such
1184-445: A signal from a CCD gives a noise background, typically a few electrons. In an EMCCD, this noise is superimposed on many thousands of electrons rather than a single electron; the devices' primary advantage is thus their negligible readout noise. The use of avalanche breakdown for amplification of photo charges had already been described in the U.S. patent 3,761,744 in 1973 by George E. Smith/Bell Telephone Laboratories. EMCCDs show
1258-422: A similar sensitivity to intensified CCDs (ICCDs). However, as with ICCDs, the gain that is applied in the gain register is stochastic and the exact gain that has been applied to a pixel's charge is impossible to know. At high gains (> 30), this uncertainty has the same effect on the signal-to-noise ratio (SNR) as halving the quantum efficiency (QE) with respect to operation with a gain of unity. This effect
1332-416: A single slice of the image, whereas a two-dimensional array, used in video and still cameras, captures a two-dimensional picture corresponding to the scene projected onto the focal plane of the sensor. Once the array has been exposed to the image, a control circuit causes each capacitor to transfer its contents to its neighbor (operating as a shift register). The last capacitor in the array dumps its charge into
1406-465: A slower maximum shutter speed of 1/4000sec. Leica subsequently announced additional upgrades: Leica announced the Leica M8.2 on 15 September 2008. The Leica M8.2 includes all the upgrades offered in the upgrade program, however the black version is coated with black paint (as opposed to the black chrome finish of the standard Leica M8) and black Leica branding dot. An auto S setting producing only JPEGs
1480-424: A time. During the readout phase, cells are shifted down the entire area of the CCD. While they are shifted, they continue to collect light. Thus, if the shifting is not fast enough, errors can result from light that falls on a cell holding charge during the transfer. These errors are referred to as "vertical smear" and cause a strong light source to create a vertical line above and below its exact location. In addition,
1554-464: A variety of astronomical applications involving low light sources and transient events such as lucky imaging of faint stars, high speed photon counting photometry, Fabry-Pérot spectroscopy and high-resolution spectroscopy. More recently, these types of CCDs have broken into the field of biomedical research in low-light applications including small animal imaging , single-molecule imaging , Raman spectroscopy , super resolution microscopy as well as
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#17327872240271628-596: Is a camera lens mount introduced in 1954 with the Leica M3 , and a range of lenses . It has been used on all the Leica M-series cameras and certain accessories (e.g. Visoflex reflex viewing attachment) up to the current film Leica M-A and digital Leica M11 cameras. This lens mount has also been used by Epson , Ricoh , Minolta , Konica , Cosina Voigtländer , Rollei , Carl Zeiss AG and Rollei Fototechnic on some of their cameras. The Leica M mount
1702-410: Is a photoactive region (an epitaxial layer of silicon), and a transmission region made out of a shift register (the CCD, properly speaking). An image is projected through a lens onto the capacitor array (the photoactive region), causing each capacitor to accumulate an electric charge proportional to the light intensity at that location. A one-dimensional array, used in line-scan cameras, captures
1776-432: Is a specialized CCD, often used in astronomy and some professional video cameras , designed for high exposure efficiency and correctness. The normal functioning of a CCD, astronomical or otherwise, can be divided into two phases: exposure and readout. During the first phase, the CCD passively collects incoming photons , storing electrons in its cells. After the exposure time is passed, the cells are read out one line at
1850-402: Is an integrated circuit containing an array of linked, or coupled, capacitors . Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a major technology used in digital imaging . In a CCD image sensor , pixels are represented by p-doped metal–oxide–semiconductor (MOS) capacitors . These MOS capacitors ,
1924-565: Is one of the major advantages of the ICCD over the EMCCD cameras. The highest performing ICCD cameras enable shutter times as short as 200 picoseconds . ICCD cameras are in general somewhat higher in price than EMCCD cameras because they need the expensive image intensifier. On the other hand, EMCCD cameras need a cooling system to cool the EMCCD chip down to temperatures around 170 K (−103 °C ). This cooling system adds additional costs to
1998-564: Is referred to as the Excess Noise Factor (ENF). However, at very low light levels (where the quantum efficiency is most important), it can be assumed that a pixel either contains an electron—or not. This removes the noise associated with the stochastic multiplication at the risk of counting multiple electrons in the same pixel as a single electron. To avoid multiple counts in one pixel due to coincident photons in this mode of operation, high frame rates are essential. The dispersion in
2072-512: Is the probability of getting n output electrons given m input electrons and a total mean multiplication register gain of g . For very large numbers of input electrons, this complex distribution function converges towards a Gaussian. Because of the lower costs and better resolution, EMCCDs are capable of replacing ICCDs in many applications. ICCDs still have the advantage that they can be gated very fast and thus are useful in applications like range-gated imaging . EMCCD cameras indispensably need
2146-422: Is the right choice. Consumer snap-shot cameras have used interline devices. On the other hand, for those applications that require the best possible light collection and issues of money, power and time are less important, the full-frame device is the right choice. Astronomers tend to prefer full-frame devices. The frame-transfer falls in between and was a common choice before the fill-factor issue of interline devices
2220-405: Is used in the construction of interline-transfer devices. Another version of CCD is called a peristaltic CCD. In a peristaltic charge-coupled device, the charge-packet transfer operation is analogous to the peristaltic contraction and dilation of the digestive system . The peristaltic CCD has an additional implant that keeps the charge away from the silicon/ silicon dioxide interface and generates
2294-681: The Kodak Apparatus Division, invented a digital still camera using this same Fairchild 100 × 100 CCD in 1975. The interline transfer (ILT) CCD device was proposed by L. Walsh and R. Dyck at Fairchild in 1973 to reduce smear and eliminate a mechanical shutter . To further reduce smear from bright light sources, the frame-interline-transfer (FIT) CCD architecture was developed by K. Horii, T. Kuroda and T. Kunii at Matsushita (now Panasonic) in 1981. The first KH-11 KENNEN reconnaissance satellite equipped with charge-coupled device array ( 800 × 800 pixels) technology for imaging
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2368-566: The LOCOS process to produce the channel stop region. Channel stops are thermally grown oxides that serve to isolate the charge packets in one column from those in another. These channel stops are produced before the polysilicon gates are, as the LOCOS process utilizes a high-temperature step that would destroy the gate material. The channel stops are parallel to, and exclusive of, the channel, or "charge carrying", regions. Channel stops often have
2442-470: The moiré artifacts can occur in scenes with closely spaced geometric patterns, such as fabric or mesh, distant buildings, balcony railings, corrugated roofing etc. The M8 uses modern metal-blade focal-plane shutter. It can fire flash synchronization at 1/250 second X-sync and has a top shutter speed of 1/8000 sec. The flash system used in the M8 is M-TTL. The camera uses a 6-bit coding system that identifies
2516-473: The photodiode to the CCD. This led to their invention of the pinned photodiode, a photodetector structure with low lag, low noise , high quantum efficiency and low dark current . It was first publicly reported by Teranishi and Ishihara with A. Kohono, E. Oda and K. Arai in 1982, with the addition of an anti-blooming structure. The new photodetector structure invented at NEC was given the name "pinned photodiode" (PPD) by B.C. Burkey at Kodak in 1984. In 1987,
2590-418: The viewfinder (for composition ) and the rangefinder (for focusing ). With a double-stroke film advance lever (later models have a single-stroke lever). The M3 was a success and over 220,000 units were sold, by the time production ended in 1966. It remains the best-selling M mount camera ever made. The M3 uses 135 film (or 35 mm film), with the canister being loaded behind a detachable bottom plate. The M3
2664-1208: The "red dot" • Manual exposure only • 3936 x 2630 max resolution • 2.5″ inch screen • 5212 x 3472 max resolution • 2.5″ inch screen • 5212 x 3472 max resolution • 2.5″ inch screen with sapphire crystal LCD glass • 3″ inch screen • Capable of capturing Full HD 1080p video • 5952 x 3976 max resolution • 3″ inch screen with sapphire crystal LCD glass • Capable of capturing Full HD 1080p video • 3″ inch screen • Wi-Fi capability • 5952 x 3992 max resolution • 3″ inch screen • Wi-Fi capability • 3″ inch screen • No removable bottom plate • 64Gb of internal memory • 2.5″ inch screen • 3″ inch screen • 3″ inch screen • Capable of capturing Full HD 1080 video • 2.5″ inch screen • Black-and-white version of
2738-410: The "red dot" • Versions: Leica MDa, Leica M4-2, Leica M4-P • First M mount with electronic Through-the-lens metering (TTL) • Leica M6 (1984–1998) • Leica M6 TTL (1998–2002): Better viewfinder and electronic flash capability • Electronic shutter control and semi-automatic mode • Removal of
2812-399: The CCD cannot be used to collect light while it is being read out. A faster shifting requires a faster readout, and a faster readout can introduce errors in the cell charge measurement, leading to a higher noise level. A frame transfer CCD solves both problems: it has a shielded, not light sensitive, area containing as many cells as the area exposed to light. Typically, this area is covered by
2886-402: The CCD concept. Michael Tompsett was awarded the 2010 National Medal of Technology and Innovation , for pioneering work and electronic technologies including the design and development of the first CCD imagers. He was also awarded the 2012 IEEE Edison Medal for "pioneering contributions to imaging devices including CCD Imagers, cameras and thermal imagers". In a CCD for capturing images, there
2960-545: The CCD to deplete, near the p–n junction and will collect and move the charge packets beneath the gates—and within the channels—of the device. CCD manufacturing and operation can be optimized for different uses. The above process describes a frame transfer CCD. While CCDs may be manufactured on a heavily doped p++ wafer it is also possible to manufacture a device inside p-wells that have been placed on an n-wafer. This second method, reportedly, reduces smear, dark current , and infrared and red response. This method of manufacture
3034-477: The CCD-G5, was released by Sony in 1983, based on a prototype developed by Yoshiaki Hagiwara in 1981. Early CCD sensors suffered from shutter lag . This was largely resolved with the invention of the pinned photodiode (PPD). It was invented by Nobukazu Teranishi , Hiromitsu Shiraki and Yasuo Ishihara at NEC in 1980. They recognized that lag can be eliminated if the signal carriers could be transferred from
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3108-404: The EMCCD camera and often yields heavy condensation problems in the application. ICCDs are used in night vision devices and in various scientific applications. An electron-multiplying CCD (EMCCD, also known as an L3Vision CCD, a product commercialized by e2v Ltd., GB, L3CCD or Impactron CCD, a now-discontinued product offered in the past by Texas Instruments) is a charge-coupled device in which
3182-513: The M9 • 3″ inch screen with sapphire crystal LCD glass • Black-and-white version of the M (Typ 240) • Capable of capturing Full HD 1080 video • 3" inch screen TFT LCD monitor • Black-and-white version of the M10 • Dedicated ISO dial with ISO 160 to ISO 100.000 • The only control on
3256-610: The PPD began to be incorporated into most CCD devices, becoming a fixture in consumer electronic video cameras and then digital still cameras . Since then, the PPD has been used in nearly all CCD sensors and then CMOS sensors . In January 2006, Boyle and Smith were awarded the National Academy of Engineering Charles Stark Draper Prize , and in 2009 they were awarded the Nobel Prize for Physics for their invention of
3330-451: The array's dark current , improving the sensitivity of the CCD to low light intensities, even for ultraviolet and visible wavelengths. Professional observatories often cool their detectors with liquid nitrogen to reduce the dark current, and therefore the thermal noise , to negligible levels. The frame transfer CCD imager was the first imaging structure proposed for CCD Imaging by Michael Tompsett at Bell Laboratories. A frame transfer CCD
3404-692: The basic building blocks of a CCD, are biased above the threshold for inversion when image acquisition begins, allowing the conversion of incoming photons into electron charges at the semiconductor-oxide interface; the CCD is then used to read out these charges. Although CCDs are not the only technology to allow for light detection, CCD image sensors are widely used in professional, medical, and scientific applications where high-quality image data are required. In applications with less exacting quality demands, such as consumer and professional digital cameras , active pixel sensors , also known as CMOS sensors (complementary MOS sensors), are generally used. However,
3478-548: The body is via the shutter speed and ISO dials • No Rear LCD Screen • The only control on the body is via the shutter speed and ISO dials Mechanical | Mechanical TTL | Electronic Controlled Shutter TTL Digital types: M = Professional | ME = Entry level | MM = Monochrom | MD = No display MR = Increased resolution CCD sensor | CMOS sensor | Video capabilities Charge-coupled device A charge-coupled device ( CCD )
3552-685: The center to corners of the image. Further details and aspects of the sensor were unveiled during the course of photokina 2006 . The Leica M8 suffered from some controversy on its release due to image quality problems reported by some users, especially an extremely high sensitivity to infrared light, which made black colors appear purple. Leica has since released a statement saying that it will send two free special UV/IR screw-on photographic filters to all future M8 purchasers, and upon request for all current M8 users. Users experiencing other image quality problems can apply to return their M8 for repair. However, this sensitivity to Infrared light has inspired
3626-426: The channel in which the photogenerated charge packets will travel. Simon Sze details the advantages of a buried-channel device: This thin layer (= 0.2–0.3 micron) is fully depleted and the accumulated photogenerated charge is kept away from the surface. This structure has the advantages of higher transfer efficiency and lower dark current, from reduced surface recombination. The penalty is smaller charge capacity, by
3700-451: The charge could be stepped along from one to the next. This led to the invention of the charge-coupled device by Boyle and Smith in 1969. They conceived of the design of what they termed, in their notebook, "Charge 'Bubble' Devices". The initial paper describing the concept in April 1970 listed possible uses as memory , a delay line, and an imaging device. The device could also be used as
3774-476: The functions due to mismatching cams. All lenses are multiplied by a 1.33x crop factor, hence a 28mm lens will act approximately like a 35mm when mounted to the M8. Because the infrared filter over the sensor is relatively weak, adding an IR-cut filter in front of the lens is recommended. In addition, Leica chooses to omit the Anti-Alias filter, citing the reason for higher resolution power of the lens. However,
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#17327872240273848-819: The gain is shown in the graph on the right. For multiplication registers with many elements and large gains it is well modelled by the equation: P ( n ) = ( n − m + 1 ) m − 1 ( m − 1 ) ! ( g − 1 + 1 m ) m exp ( − n − m + 1 g − 1 + 1 m ) if n ≥ m {\displaystyle P\left(n\right)={\frac {\left(n-m+1\right)^{m-1}}{\left(m-1\right)!\left(g-1+{\frac {1}{m}}\right)^{m}}}\exp \left(-{\frac {n-m+1}{g-1+{\frac {1}{m}}}}\right)\quad {\text{ if }}n\geq m} where P
3922-506: The image sensor for storage. In this device, only one pixel shift has to occur to transfer from image area to storage area; thus, shutter times can be less than a microsecond and smear is essentially eliminated. The advantage is not free, however, as the imaging area is now covered by opaque strips dropping the fill factor to approximately 50 percent and the effective quantum efficiency by an equivalent amount. Modern designs have addressed this deleterious characteristic by adding microlenses on
3996-497: The incident light. Most common types of CCDs are sensitive to near-infrared light, which allows infrared photography , night-vision devices, and zero lux (or near zero lux) video-recording/photography. For normal silicon-based detectors, the sensitivity is limited to 1.1 μm. One other consequence of their sensitivity to infrared is that infrared from remote controls often appears on CCD-based digital cameras or camcorders if they do not have infrared blockers. Cooling reduces
4070-467: The invention and began development programs. Fairchild's effort, led by ex-Bell researcher Gil Amelio, was the first with commercial devices, and by 1974 had a linear 500-element device and a 2D 100 × 100 pixel device. Peter Dillon, a scientist at Kodak Research Labs, invented the first color CCD image sensor by overlaying a color filter array on this Fairchild 100 x 100 pixel Interline CCD starting in 1974. Steven Sasson , an electrical engineer working for
4144-431: The large quality advantage CCDs enjoyed early on has narrowed over time and since the late 2010s CMOS sensors are the dominant technology, having largely if not completely replaced CCD image sensors. The basis for the CCD is the metal–oxide–semiconductor (MOS) structure, with MOS capacitors being the basic building blocks of a CCD, and a depleted MOS structure used as the photodetector in early CCD devices. In
4218-411: The late 1960s, Willard Boyle and George E. Smith at Bell Labs were researching MOS technology while working on semiconductor bubble memory . They realized that an electric charge was the analogy of the magnetic bubble and that it could be stored on a tiny MOS capacitor. As it was fairly straightforward to fabricate a series of MOS capacitors in a row, they connected a suitable voltage to them so that
4292-451: The lens in use to the electronics built into M8 body. The code is included on all current Leica lenses. To prevent excessive vignetting due to closer lens mount than in a DSLR and thus higher light rays angle on the sensor periphery, offset micro-lenses are used on the CCD. The 6-bit code on lenses gives information about optic vignetting characteristics, permitting software adjustment. The M8 uses Adobe DNG as its raw data format and
4366-467: The multiplied electrons back to photons which are guided to the CCD by a fiber optic or a lens. An image intensifier inherently includes a shutter functionality: If the control voltage between the photocathode and the MCP is reversed, the emitted photoelectrons are not accelerated towards the MCP but return to the photocathode. Thus, no electrons are multiplied and emitted by the MCP, no electrons are going to
4440-413: The other in the mentioned sequence. The photons which are coming from the light source fall onto the photocathode, thereby generating photoelectrons. The photoelectrons are accelerated towards the MCP by an electrical control voltage, applied between photocathode and MCP. The electrons are multiplied inside of the MCP and thereafter accelerated towards the phosphor screen. The phosphor screen finally converts
4514-491: The output of the CCD, and this must be taken into consideration in satellites using CCDs. The photoactive region of a CCD is, generally, an epitaxial layer of silicon . It is lightly p doped (usually with boron ) and is grown upon a substrate material, often p++. In buried-channel devices, the type of design utilized in most modern CCDs, certain areas of the surface of the silicon are ion implanted with phosphorus , giving them an n-doped designation. This region defines
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#17327872240274588-450: The output of the charge amplifier into a low-pass filter), which is then processed and fed out to other circuits for transmission, recording, or other processing. Before the MOS capacitors are exposed to light, they are biased into the depletion region; in n-channel CCDs, the silicon under the bias gate is slightly p -doped or intrinsic. The gate is then biased at a positive potential, above
4662-407: The phosphor screen and no light is emitted from the image intensifier. In this case no light falls onto the CCD, which means that the shutter is closed. The process of reversing the control voltage at the photocathode is called gating and therefore ICCDs are also called gateable CCD cameras. Besides the extremely high sensitivity of ICCD cameras, which enable single photon detection, the gateability
4736-403: The raw converter Capture One LE (included with the camera). The KAF-10500 is a CCD imaging sensor designed by US photographic company Eastman Kodak . In September 2006 it was announced that the sensor was to be used in the M8 camera, having been specifically designed for this application. Its size is 18x27 mm (APS-H) and it has 10.3 million pixels of size 6.8 μm. Compared to 35mm film , it has
4810-406: The surface of the device to direct light away from the opaque regions and on the active area. Microlenses can bring the fill factor back up to 90 percent or more depending on pixel size and the overall system's optical design. The choice of architecture comes down to one of utility. If the application cannot tolerate an expensive, failure-prone, power-intensive mechanical shutter, an interline device
4884-407: The threshold for strong inversion, which will eventually result in the creation of an n channel below the gate as in a MOSFET . However, it takes time to reach this thermal equilibrium: up to hours in high-end scientific cameras cooled at low temperature. Initially after biasing, the holes are pushed far into the substrate, and no mobile electrons are at or near the surface; the CCD thus operates in
4958-456: The total usable integration time. The accumulation of electrons at or near the surface can proceed either until image integration is over and charge begins to be transferred, or thermal equilibrium is reached. In this case, the well is said to be full. The maximum capacity of each well is known as the well depth, typically about 10 electrons per pixel. CCDs are normally susceptible to ionizing radiation and energetic particles which causes noise in
5032-554: Was a simple 8-bit shift register, reported by Tompsett, Amelio and Smith in August 1970. This device had input and output circuits and was used to demonstrate its use as a shift register and as a crude eight pixel linear imaging device. Development of the device progressed at a rapid rate. By 1971, Bell researchers led by Michael Tompsett were able to capture images with simple linear devices. Several companies, including Fairchild Semiconductor , RCA and Texas Instruments , picked up on
5106-535: Was added to the shutter speed dial. Leica also introduced the M8.2 Safari edition package, limited to a production run of 500. The package includes an olive green painted Leica M8.2, a silver-finished Leica Elmarit -M 28mm f/2.8 ASPH lens and a matching Billingham camera case. Digital types: M = Professional | ME = Entry level | MM = Monochrom | MD = No display MR = Increased resolution CCD sensor | CMOS sensor | Video capabilities Leica M-mount The Leica M mount
5180-479: Was addressed. Today, frame-transfer is usually chosen when an interline architecture is not available, such as in a back-illuminated device. CCDs containing grids of pixels are used in digital cameras , optical scanners , and video cameras as light-sensing devices. They commonly respond to 70 percent of the incident light (meaning a quantum efficiency of about 70 percent) making them far more efficient than photographic film , which captures only about 2 percent of
5254-450: Was demonstrated by Gil Amelio , Michael Francis Tompsett and George Smith in April 1970. This was the first experimental application of the CCD in image sensor technology, and used a depleted MOS structure as the photodetector. The first patent ( U.S. patent 4,085,456 ) on the application of CCDs to imaging was assigned to Tompsett, who filed the application in 1971. The first working CCD made with integrated circuit technology
5328-948: Was followed by many other M mount cameras, released over 40 years, with many of the basic concepts remaining in these designs. With the introduction of the Through-the-lens metering (TTL) in the Leica M5 and the digital Leica M8 being the most notable innovations since then. The lenses for the M mount were also introduced in 1954 and were based on the earlier M39 thread mount. Almost all M mount lenses are Prime lenses . These lenses are divided by Leica based on their maximum aperture number (also known as f-number ). They are distinguished by their names: • 220,000 produced in Germany • Around 1,500 produced in Canada • Introduction of
5402-548: Was introduced in 1954 at that year's Photokina show, with the Leica M3 as its first camera. The 'M' stands for Messsucher or rangefinder in German. This new camera abandoned the M39 lens mount in favour of a new bayonet mount. The bayonet mount allowed lenses to be changed more quickly and made the fitting more secure. Other innovations introduced by the M3 included a single window for
5476-471: Was launched in December 1976. Under the leadership of Kazuo Iwama , Sony started a large development effort on CCDs involving a significant investment. Eventually, Sony managed to mass-produce CCDs for their camcorders . Before this happened, Iwama died in August 1982. Subsequently, a CCD chip was placed on his tombstone to acknowledge his contribution. The first mass-produced consumer CCD video camera ,
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