Secure Digital abbreviated as SD, is a non-volatile memory card format developed by the SD Card Association for use in portable devices. The standard was introduced in August 1999 by joint efforts between SanDisk and Toshiba as an improvement over MultiMediaCards, has become the industry standard; the three companies formed SD-3C, LLC, a company that licenses and enforces intellectual property rights associated with SD memory cards and SD host and ancillary products. The companies formed the SD Association, a non-profit organization, in January 2000 to promote and create SD Card standards. SDA today has about 1,000 member companies; the SDA uses several trademarked logos owned and licensed by SD-3C to enforce compliance with its specifications and assure users of compatibility. In 1999, SanDisk and Toshiba agreed to develop and market the Secure Digital Memory Card; the card was derived from the MultiMediaCard and provided digital rights management based on the Secure Digital Music Initiative standard and for the time, a high memory density.
It was designed to compete with the Memory Stick, a DRM product that Sony had released the year before. Developers predicted; the trademarked SD logo was developed for the Super Density Disc, the unsuccessful Toshiba entry in the DVD format war. For this reason the D within the logo resembles an optical disc. At the 2000 Consumer Electronics Show trade show, the three companies announced the creation of the SD Association to promote SD cards; the SD Association, headquartered in San Ramon, United States, started with about 30 companies and today consists of about 1,000 product manufacturers that make interoperable memory cards and devices. Early samples of the SD Card became available in the first quarter of 2000, with production quantities of 32 and 64 MB cards available three months later; the miniSD form was introduced at March 2003 CeBIT by SanDisk Corporation which announced and demonstrated it. The SDA adopted the miniSD card in 2003 as a small form factor extension to the SD card standard.
While the new cards were designed for mobile phones, they are packaged with a miniSD adapter that provides compatibility with a standard SD memory card slot. In September 2006, SanDisk announced the 4 GB miniSDHC. Like the SD and SDHC, the miniSDHC card has the same form factor as the older miniSD card but the HC card requires HC support built into the host device. Devices that support miniSDHC work with miniSD and miniSDHC, but devices without specific support for miniSDHC work only with the older miniSD card. Since 2008, miniSD cards were no longer produced; the microSD removable miniaturized Secure Digital flash memory cards were named T-Flash or TF, abbreviations of TransFlash. TransFlash and microSD cards are functionally identical allowing either to operate in devices made for the other. SanDisk had conceived microSD when its chief technology officer and the chief technology officer of Motorola concluded that current memory cards were too large for mobile phones; the card was called T-Flash, but just before product launch, T-Mobile sent a cease-and-desist letter to SanDisk claiming that T-Mobile owned the trademark on T-, the name was changed to TransFlash.
At CTIA Wireless 2005, the SDA announced the small microSD form factor along with SDHC secure digital high capacity formatting in excess of 2 GB with a minimum sustained read and write speed of 17.6 Mbit/s. SanDisk induced the SDA to administer the microSD standard; the SDA approved the final microSD specification on July 13, 2005. MicroSD cards were available in capacities of 32, 64, 128 MB; the Motorola E398 was the first mobile phone to contain a TransFlash card. A few years their competitors began using microSD cards; the SDHC format, announced in January 2006, brought improvements such as 32 GB storage capacity and mandatory support for FAT32 filesystems. In April, the SDA released a detailed specification for the non-security related parts of the SD memory card standard and for the Secure Digital Input Output cards and the standard SD host controller. In January 2009, the SDA announced the SDXC family, which supports cards up to 2 TB and speeds up to 300 MB/s, it features mandatory support for the exFAT filesystem.
SDXC was announced at Consumer Electronics Show 2009. At the same show, SanDisk and Sony announced a comparable Memory Stick XC variant with the same 2 TB maximum as SDXC, Panasonic announced plans to produce 64 GB SDXC cards. On March 6, Pretec introduced the first SDXC card, a 32 GB card with a read/write speed of 400 Mbit/s, but only early in 2010 did compatible host devices come onto the market, including Sony's Handycam HDR-CX55V camcorder, Canon's EOS 550D Digital SLR camera, a USB card reader from Panasonic, an integrated SDXC card reader from JMicron. The earliest laptops to integrate SDXC card readers relied on a USB 2.0 bus, which does not have the bandwidth to support SDXC at full speed. In early 2010, commercial SDXC cards appeared from Toshiba and SanDisk. In early 2011, Centon Electronics, Inc. and Lexar began shipping SDXC cards rated at Speed Class 10. Pretec offered cards from 8 GB to 128 GB rated at Speed Class 16. In September 2011, SanDisk released a 64 GB microSDXC card. Kingmax released a comparable product in 2011.
In April 2012, Panasonic introduced MicroP2 card format for professional video applications. The cards are full-size SDHC or SDXC UHS-II cards, rated at UHS Speed Class U1. An adapter allows MicroP
CompactFlash is a flash memory mass storage device used in portable electronic devices. The format was specified and the devices were first manufactured by SanDisk in 1994. CompactFlash became one of the most successful of the early memory card formats, surpassing Miniature Card and SmartMedia. Subsequent formats, such as MMC/SD, various Memory Stick formats, xD-Picture Card offered stiff competition. Most of these cards are smaller than CompactFlash while offering comparable capacity and speed. Proprietary memory card formats for use in professional audio and video, such as P2 and SxS, are faster, but physically larger and more costly. CompactFlash remains popular and is supported by many professional devices and high-end consumer devices; as of 2017, both Canon and Nikon use CompactFlash for their flagship digital still cameras. Canon chose CompactFlash as the recording medium for its professional high-definition tapeless video cameras. Ikegami professional video cameras can record digital video onto CompactFlash cards through an adaptor.
Traditional CompactFlash cards use the Parallel ATA interface, but in 2008, a variant of CompactFlash, CFast was announced. CFast is based on the Serial ATA interface. In November 2010, SanDisk and Nikon presented a next generation card format to the CompactFlash Association; the new format has a similar form factor to CF/CFast but is based on the PCI Express interface instead of Parallel ATA or Serial ATA. With potential read and write speeds of 1 Gbit/s and storage capabilities beyond 2 TiB, the new format is aimed at high-definition camcorders and high-resolution digital cameras, but the new cards are not backward compatible with either CompactFlash or CFast; the XQD card format was announced by the CompactFlash Association in December 2011. There are two main subdivisions of CF cards, 3.3 mm-thick type I and 5 mm-thick type II. The type II slot is used by miniature hard drives and some other devices, such as the Hasselblad CFV Digital Back for the Hasselblad series of medium format cameras.
There are four main card speeds: original CF, CF High Speed, faster CF 3.0 standard and the faster CF 4.0 standard adopted as of 2007. CompactFlash was built around Intel's NOR-based flash memory, but has switched to NAND technology. CF is among the oldest and most successful formats, has held a niche in the professional camera market well, it has benefited from both a better cost to memory-size ratio and, for much of the format's life greater available capacity than other formats. CF cards can be used directly in a PC Card slot with a plug adapter, used as an ATA or PCMCIA storage device with a passive adapter or with a reader, or attached to other types of ports such as USB or FireWire; as some newer card types are smaller, they can be used directly in a CF card slot with an adapter. Formats that can be used this way include SD/MMC, Memory Stick Duo, xD-Picture Card in a Type I slot and SmartMedia in a Type II slot, as of 2005; some multi-card readers use CF for I/O as well. The CompactFlash interface is a 50-pin subset of the 68-pin PCMCIA connector.
"It can be slipped into a passive 68-pin PCMCIA Type II to CF Type I adapter that meets PCMCIA electrical and mechanical interface specifications", according to compactflash.org. The interface operates, depending on the state of a mode pin on power-up, as either a 16-bit PC Card or as an IDE interface. Unlike the PC Card interface, no dedicated programming voltages are provided on the CompactFlash interface. CompactFlash IDE mode defines an interface, smaller than, but electrically identical to, the ATA interface; the CF device appears to the host device as if it were a hard disk. CF devices operate at 3.3 volts or 5 volts, can be swapped from system to system. CompactFlash supports 28-bit logical block addressing. CF cards with flash memory are able to cope with rapid changes in temperature. Industrial versions of flash memory cards can operate at a range of −45 °C to +85 °C. NOR-based flash has lower density than newer NAND-based systems, CompactFlash is therefore the physically largest of the three memory card formats introduced in the early 1990s, being derived from the JEIDA/PCMCIA Memory Card formats.
The other two are Miniature SmartMedia. However, CF did switch to NAND type memory later; the IBM Microdrive format made by Hitachi, implements the CF Type II interface, but is a hard disk drive as opposed to solid-state memory. Seagate made CF HDDs. CompactFlash IDE emulation speed is specified in "x" ratings, e.g. 8x, 20x, 133x. This is the same system used for CD-ROMs and indicates the maximum transfer rate in the form of a multiplier based on the original audio CD data transfer rate, 150 kB/s. R = K ⋅ 150 kB/s where R = transfer rate, K = speed rating. For example, 133x rating means transfer speed of: 133 × 150 kB/s ≈ 20 MB/s; these are manufacturer speed ratings. Actual transfer speed may be lower, than shown on the card depending on several factors; the speed rating quoted is always the read speed, while write speed is slower. For reads, the onboard controller first powers up the memory chips from standby. Reads are in parallel, error correction is done on the data transferred through the interface 16 bits at a time.
Error checking is required due to soft read errors. Writes require powerup from standby, wear leveling calculation, a block erase of the area to be written to, E
The image circle is the cross section of the cone of light transmitted by a lens or series of lenses onto the image plane. When this light strikes a perpendicular target such as photographic film or a digital camera sensor, it forms a circle of light – the image circle. Various sensor aspect ratios may be used which all fit inside the same image circle, 3:2, 4:3, 16:9, etc. A lens to be used on a camera that provides movements must have an image circle larger than the size of the image format. To avoid vignetting, a photographer using a view camera must ensure that the area remains within the image circle. Film format Image sensor format Format factor Adams, Ansel. 1980. The Camera; the New Ansel Adams Basic Photography Series/Book 1. Ed. Robert Baker. Boston: New York Graphic Society. ISBN 0-8212-1092-0 Ray, Sidney F. 2000. The geometry of image formation. In The Manual of Photography: Photographic and Digital Imaging, 9th ed. Ed. Ralph E. Jacobson, Sidney F. Ray, Geoffrey G. Atteridge, Norman R. Axford.
Oxford: Focal Press. ISBN 0-240-51574-9 Ray, Sidney F. 2002. Applied Photographic Optics, 3rd ed. Oxford: Focal Press ISBN 0-240-51540-4 Langford, Michael J. Basic Photography, 3rd ed, 63–64. Garden City, NY: Amphoto, 1973. ISBN 0-8174-0640-9 Ray, Sidney F. Photographic Lenses and Optics, 125. Oxford: Focal Press, 1994. ISBN 0-240-51387-8 Stroebel, Leslie. View Camera Technique, 3rd ed, 62–67. London: Focal Press, 1976. ISBN 0-240-50901-3
A bayonet mount or bayonet connector is a fastening mechanism consisting of a cylindrical male side with one or more radial pins, a female receptor with matching L-shaped slot and with spring to keep the two parts locked together. The slots are shaped like a capital letter L with serif; the bayonet mount is the standard light bulb fitting in the United Kingdom and in many countries that were members of the British Empire including Pakistan, Hong Kong, Fiji India, Sri Lanka and New Zealand, parts of the Middle East and Africa and France and Greece. To couple the two parts, the pin on the male are aligned with the slot on the female and the two pushed together. Once the pins reach the bottom of the slot, one or both parts are rotated so that the pin slides along the horizontal arm of the L until it reaches the "serif"; the spring pushes the male connector up into the "serif" to keep the pin locked into place. A practised user can connect them and, unlike screw connectors, they are not subject to cross-threading.
To disconnect, the two parts are pushed together to move the pin out of the "serif" while twisting in the opposite direction than for connecting, pulling apart. The strength of the joint comes from the strength of the pins and the L slots, the spring. To disengage unintentionally, the pins must break, the sleeve into which the connector slides must be distorted or torn enough to free the pins, or the spring must fail and allow the connector to be pushed down and rotate - for example due to vibration, it is possible to rotate it, but not far enough to engage and lock. Bayonet electrical connectors are used in the same applications where other connectors are used, to transmit either power or signals. Bayonet connections can be made faster than screw connections, more securely than push-fit connections, they may be used to connect two cables, or to connect a cable to a connector on the panel of a piece of equipment. The coupling system is made of two bayonet ramps machined on the external side of the receptacle connector and 2 stainless steel studs mounted inside the plug connector’s coupling nut.
Several classes of electrical cable connectors, including audio and data cables use bayonet connectors. Examples include BNC, C, ST connectors; the first documented use of this type of fitting may be by Al-Jazari in the 13th century, who used it to mount candles into his candle-clocks. This type of fitting was used for soldiers who needed to mount bayonets to the ends of their rifles, hence the name; the bayonet light bulb mount is the standard fitting in many former members of the British Empire including the United Kingdom, India and New Zealand, Hong Kong, as well as parts of the Middle East and Africa. The standard size is B22d-2 referred to in the context of lighting as BC or B22. Older installations in some other countries, including France and Greece use this base. First developed by St. George Lane Fox-Pitt in the UK and improved upon by the Brush Electric Company from the late 1870s onward, standard bulbs have two pins on opposite sides of the cap. Examples of three-pin bulbs are found in mercury street lamps and fireglow bulbs in some older models of electric radiative heater.
Older railway carriages in the UK made use of a 3 pin bulb base to discourage theft. Bayonet cap bulbs are very common worldwide in applications where vibration may loosen screw-mount bulbs, such as automotive lighting and other small indicators, in many flashlights. In many other countries the Edison screw base is used for lighting; some bulbs may have offset lugs to ensure they can be only inserted in one orientation, for example the 1157 automobile tail-light which has two different filaments to act as both a tail light and a brake light. In this bulb each filament has a different brightness and is connected to a separate contact on the bottom of the base. Newer bulbs use a wedge base; some special-purpose bulbs, such as infra-red, have 3 pins 120 degrees apart to prevent them being used in any but the intended socket. Bayonet bases or caps are abbreviated to BA with a number after; the number refers to the diameter of the base. BA15, a 15 mm base, can be referred to as SBC standing for small bayonet cap.
The lower-case letter s or d specifies whether the bulb has double contacts. While G indicates bi-pin, those listed above have a twist-lock, but with parallel pins from the end instead of opposing pins on the side; these are the available sizes in the UK: Of these, only
Sony SLT camera
Single-Lens Translucent is a Sony proprietary designation for Sony Alpha cameras which employ a pellicle mirror, electronic viewfinder, phase-detection autofocus system. They employ the same Minolta A-mount as Sony Alpha DSLR cameras. Sony SLT cameras have a semi-transparent fixed mirror which diverts a portion of incoming light to a phase-detection autofocus sensor, while the remaining light strikes a digital image sensor; the image sensor feeds the electronic viewfinder, records still images and video on command. The utility of the SLT design is to allow full-time phase-detection autofocus during electronic viewfinder, live view, video recording operation. With the advent of digital image sensors with integrated phase-detection, the SLT design is no longer required to accomplish this goal, as evidenced by cameras such as the Sony NEX-5R, Fujifilm X-100s, Nikon 1; the term "translucent" is a misnomer for the actual SLT design, which employs a pellicle mirror, not translucent. Pellicle mirrors have been used in single-lens reflex cameras from at least the 1960s.
All of the above cameras record 1920x1080 video in MPEG-4, AVCHD or H. 264 formats. The Alpha 99II records 4k video at 100Mbit/s with full sensor read-out. Source: summarised from the full comparison table at DP Review. Sony ILCA camera Digital single-lens reflex camera
A hot shoe is a mounting point on the top of a camera to attach a flash unit and other compatible accessories. It takes the form of an angled metal bracket surrounding a metal contact point which shorts an electrical connection between camera and accessory for standard, brand-independent flash synchronization; the hot shoe is a development of the standardised "accessory shoe", with no flash contacts fitted to cameras to hold accessories such as a rangefinder, or flash connected by a cable. The dimensions of the hot shoe are defined by the International Organization for Standardization in ISO 518:2006. Details such as trigger voltage are not standardised; the hot shoe is shaped somewhat like an squared-off "U" of metal. The matching adapter on the bottom of the flash unit slides in from the back of the camera and is sometimes secured by a clamping screw on the flash. In the center of the "U" is a metal contact point; this is used for brand-independent flash synchronization. The metal of the shoe and the metal of the contact are electrically isolated from each other.
To fire the flash, these two pieces are shorted together. The flash unit sets up a circuit between shoe and contact—when it is completed by the camera, the flash fires. In addition to the central contact point, many cameras have additional metal contacts within the "U" of the hot shoe; these are proprietary connectors that allow for more communication between the camera and a "dedicated flash". A dedicated flash can communicate information about its power rating to the camera, set camera settings automatically, transmit color temperature data about the emitted light, can be commanded to light a focus-assist light or fire a lower-powered pre-flash for focus-assist, metering assist or red-eye effect reduction; the physical dimensions of the "standard hot shoe" are defined by the International Organization for Standardization ISO 518:2006. Before the 1970s, many cameras had an "accessory shoe" intended to hold accessories including flashes that connected electrically via a cable, external light meters, special viewfinders, or rangefinders.
These earlier accessory shoes had no electrical contacts. Canon, Nikon and Pentax use the standard ISO hot shoe with various proprietary electronic extensions. In 2014, camera accessory manufacturer Cactus combined these electronic extensions into a multi-brand hot shoe on their wireless flash transceiver V6. With multi-brand ISO hot shoe and flashes from different manufacturers work together. In 1988 Minolta switched to use a 4-pin proprietary slide-on auto-lock "iISO" connector. A compatible 7-pin variant, which allows battery-less accessories to be powered by the camera's battery were made, but not used. Konica Minolta and Sony Alpha digital SLR cameras are based on Minolta designs and used the same connector named Auto-lock Accessory Shoe, as well up to 2012. Since the electrical protocol remained compatible, TTL and non-TTL adapters exist to adapt ISO-based flashes to iISO hotshoes and vice versa. Sony used a variety of other proprietary hotshoes for other digital cameras, including the ISO-based 6-pin Cyber-shot hotshoe, the 16-pin Active Interface Shoe and the ISO-based 16-pin Intelligent Accessory Shoe.
Some of their NEX cameras used a proprietary Smart Accessory Terminal. In September 2012, Sony announced a new ISO-based 21+3 pin Multi Interface Shoe for use with their future digital cameras of the Alpha, NEX, Handycam, NXCAM and Cyber-shot series; this quick-lock hotshoe is mechanically and electrically compatible with a standard 2-pin ISO-518 hotshoe, but electrically compatible with the previous Auto-lock Accessory Shoe with extensions, so that passive adapters ADP-AMA and ADP-MAA allow to use digital-ready iISO flashes on new cameras and some new Multi Interface Shoe equipment on older cameras, while providing compatibility with standard ISO-based equipment as well. Canon uses a non-ISO-based 13+1 pin hot shoe, named Mini Advanced Shoe on some of its camcorders. An internal camera circuit shorts the center shoe mount to trigger the flash; the magnitude and polarity of the voltage between the contacts on the flash in the open-circuit condition has varied between different flash units. However, with more recent cameras with electronic triggering, excessive or insufficient voltage, or incorrect polarity can cause failure to fire, or damage the camera.
The ISO 10330 specification allows for a trigger voltage of 24 volts. Some manufacturers Canon, ask for no more than 6 volts. Flash units designed for modern cameras use voltages which are safe and effective, but some older flashes have much higher voltages, up to hundreds of volts, which damage electronic triggering circuits; some use negative DC polarity, or AC. iISO hotshoe contacts are only protected up to ca. 5 volts in some cameras. Minolta documented all their cameras' electronically controlled PC terminals and ISO hot shoes to be protected up to 400 volts, it is possible to connect an older high-voltage triggering flash to a camera which can only tolerate 5 or 6 volts through an adaptor containing the necessary voltage protection circuitry using a high power TRIAC. Such adapters drain power from the flash's trigger voltage and therefore do not need a power supply of their own. In order to avoid dangerous loops when connecting equipment in complex studio setups, better adapters offer voltage protection and galvanic isolation of the units.
Such adapters will ensure that there is no electrica
The E-mount is a lens mount designed by Sony for their NEX and ILCE series of camcorders and mirrorless cameras. The E-mount supplements Sony's A-mount, allowing the company to develop more compact imaging devices while maintaining compatibility with 35mm sensors. E-mount achieves this by: Minimizing mechanical complexity, removing mechanical aperture and focus drive. Shortening the flange focal distance to 18 mm compared with earlier offerings from Sony which used 44.5 mm. Reducing the radius of the flange; the short flange focal distance prohibits the use of an optical viewfinder as a mirror box mechanism cannot be included in this reduced distance. Therefore all E-mount cameras use an electronic viewfinder. E-mount was implemented on the Sony α NEX-3 and NEX-5 consumer-targeted devices with APS-C sized sensors. E-mount integration into Sony camcorder products was provided with the Sony Handycam NEX-VG10. On 24 August 2011, new products were announced the NEX-5N as a successor for the NEX-5, the NEX-7 as a prosumer product, as well as the NEX-VG20 as the successor to the NEX-VG10.
The Sony E-mount was brought to the 35 millimeter video camera market with the Sony NEX-FS100. The first third-party camera to use the E-mount was the Hasselblad Lunar, announced at photokina on 18 September 2012 and released in early 2013. In September 2013, Sony announced the first model from new ILCE series, the Sony α3000. In October 2013, the first models with full-frame sensor size were released, the Sony α7 and Sony α7R. On 19 April 2017, Sony revealed their new model Model ILCE-9, the Sony α9, characterized as a professional mirrorless camera system. In September 2017, Sony revealed their high-end camera for video-production, VENICE - a 6K 16bit RAW recording camera. List of Sony E-mount cameras: On 8 February 2011, Sony announced the release of the specifications for the E-mount lens system, allowing for third-party lens makers to create lenses for the NEX cameras without having to pay royalties; the mount specifications have been released to registered parties since April 2011. Getting a license for the specifications requires approval by Sony and the signing of a non-disclosure agreement.
The construction of full frame manual focus prime lenses without any electronics is easier and less costly than the construction of electronic full frame autofocus lenses of any kind. Additionally, the E-mount Sony α7 series are the only full frame mirrorless cameras and have more electronic aids for manual focusing than full-frame DSLRs. Both these facts have encouraged lesser known lens companies to construct full frame prime lenses with E-mount. Numerous affordable sharp full-format manual prime lenses with big apertures are available with E-mount. Anhui ChangGeng Optical Technology Company Carl Zeiss AG Cosina Co. Ltd. Handevision Samyang Optics / Rokinon Sigma Corporation Shenyang Zhongyi Optical and Electronic Company Shenzhen Neewer SLR Magic Tamron Co. Ltd. Tokina Venus Optics Voigtländer Yasuhara Zunow 7Artisans Due to the short flange focal distance of the Sony E-mount, many lenses can be adapted to be used on the Sony E-mount, although a crop factor will have to be taken into account for all cameras with APS-C or Super-35mm sensor format.
Additionally, with the introduction of in-camera image stabilization to Sony's newer mirrorless cameras, any adapted lens can be image stabilized. Nearly all manual lenses can be attached with simple ring-like adapters to Sony's mirrorless cameras, such as for Canon FD, Minolta MC/MD, Leica M, many others. Manual focus lenses that transmit EXIF data will require an adapter with electronic contacts, which are more expensive to produce. Adapting autofocus lenses to Sony's older E-mount cameras can be ineffective due to the inability of the camera body to lock-on to a subject, resulting in either hunting or missed focus; this has been remedied in recent years with improved lens adapter performance, as well as the introduction of faster, more accurate autofocusing systems to Sony's more recent cameras. Any A-mount lenses can be used via the Sony LA-EA1, LA-EA2, LA-EA3, or LA-EA4 mount adapters, which provide electronic contacts and electro-mechanical diaphragm control, they allow the camera body to control the aperture of the lens and provide automatic exposure and Exif data support.
LA-EA1: APS-C format only. LA-EA2: APS-C format only. However, their translucent-mirror design requires an optical element in the light path and thus causes a light fall-off of about 30% and a slight decrease in image quality for the autofocus to work. LA-EA3: full-frame format compatible. LA-EA4: full-frame format compatible, it has an internal autofocus motor and a second internal aperture motor for older screw driven autofocus a-mount lenses. It supports all auto focus A-mount lenses from Sony, Tamron and the older Minolta lenses. Full manual focus Minolta MD/MC won't work on this adapter, it is the only adapter of all mirror