A test card , also known as a test pattern or start-up/closedown test , is a television test signal, typically broadcast at times when the transmitter is active but no program is being broadcast (often at sign-on and sign-off ).
109-574: Used since the earliest TV broadcasts, test cards were originally physical cards at which a television camera was pointed, allowing for simple adjustments of picture quality. Such cards are still often used for calibration, alignment, and matching of cameras and camcorders . From the 1950s, test card images were built into monoscope tubes which freed up the use of TV cameras which would otherwise have to be rotated to continuously broadcast physical test cards during downtime hours. Electronically generated test patterns, used for calibrating or troubleshooting
218-478: A DVCPro signal on interchangeable flash memory media. Several other data storage device recording systems were introduced, notably XDCAM from Sony . Sony also introduced SxS (S-by-S), a flash memory standard compliant to the Sony and Sandisk -created ExpressCard standard. Eventually flash storage largely supplanted other forms of recording media. In 2000s, major manufacturers like Sony and Philips introduced
327-742: A Radiodiffusion-Télévision Française 819-line test card introduced in 1953. In North America, most test cards such as the famous Indian-head test pattern of the 1950s and 1960s have long since been relegated to history. The SMPTE color bars occasionally turn up, but with most North American broadcasters now following a 24-hour schedule, these too have become a rare sight. With the introduction of color TV, electronically generated test cards were introduced. They are named after their generating equipment (ex: Grundig VG1000, Philips PM5544 , Telefunken FuBK , etc.), TV station (ex: BBC test card ) or organization (ex: SMPTE color bars , EBU colour bars ). In developed countries such as Australia , Canada ,
436-493: A crane , thus making the cameras much more versatile than previous generations of studio cameras. These cameras have a tally light , a small signal-lamp used that indicates, for the benefit of those being filmed as well as the camera operator , that the camera is 'live' – i.e. its signal is being used for the 'main program' at that moment. ENG ( electronic news gathering ) video cameras were originally designed for use by news camera operators . While they have some similarities to
545-474: A television camera even though its use has spread beyond television ) is a high-end device for creating electronic moving images (as opposed to a movie camera , that earlier recorded the images on film ). Originally developed for use in television studios or with outside broadcast trucks , they are now also used for music videos , direct-to-video movies (see digital movie camera ), corporate and educational videos, wedding videos, among other uses. Since
654-485: A triax , fibre optic or the almost obsolete multicore cable . The CCU, along with genlock and other equipment, is installed in the central apparatus room (CAR) of the television studio. A remote control panel in the production control room (PCR) for each camera is then used by the vision engineer(s) to balance the pictures. When used outside a formal television studio in outside broadcasting (OB), they are often on tripods that may or may not have wheels (depending on
763-509: A vectorscope , allowing chroma and tint to be precisely adjusted between generations of videotape or network feeds. SMPTE bars—and several other test cards—include analog black (a flat waveform at 7.5 IRE , or the NTSC setup level ), full white (100 IRE), and a "sub-black", or "blacker-than-black" (at 0 IRE), which represents the lowest low-frequency transmission voltage permissible in NTSC broadcasts (though
872-563: A vectorscope , allowing precise adjustments of image equipment. The audio broadcast while test cards are shown is typically a sine wave tone, radio (if associated or affiliated with the television channel) or music (usually instrumental , though some also broadcast with jazz or popular music ). Digitally generated cards came later, associated with digital television , and add a few features specific of digital signals, like checking for error correction , chroma subsampling , aspect ratio signaling , surround sound , etc. More recently,
981-421: A common sight, test cards are now only rarely seen outside of television studios, post-production, and distribution facilities. In particular, they are no longer intended to assist viewers in calibration of television sets. Several factors have led to their demise for this purpose: For custom-designed video installations, such as LED displays in buildings or at live events, some test images are custom-made to fit
1090-428: A mile or more. As the camera innards shrunk, the electronics no longer dictated the size of the enclosure, however the box shape remained, as it is necessary to hold the large studio lenses, teleprompters , electronic viewfinder (EVF), and other paraphernalia needed for studio and sports production. Electronic Field Production cameras were often mounted in studio configurations inside a mounting cage. This cage supported
1199-572: A number of territories with less than a million inhabitants, most of which are UK or US territories, or have close historical ties with the UK or US: American Samoa, Bahamas, Belize, British Virgin Islands, Cayman Islands, Dominica, Falkland Islands, Grenada, Guam, The N. Mariana Islands, Samoa, St. Lucia, St. Vincent & The Grenadines, St. Helena, St. Kitts & Nevis, the Turks & Caicos Islands, and
SECTION 10
#17328768411271308-452: A one piece camera containing all the electronics to output a broadcast quality composite video signal. A separate videotape recording unit was still required. Electronic news-gathering (ENG) cameras replaced the 16mm film cameras for TV news production from the 1970s onwards because the cost of shooting on film was significantly more than shooting on a reusable tape. Portable video tape production also enabled much faster turnaround time for
1417-628: A separate VTR was still required to record the camera's video output. Typically this was either a portable 1" reel to reel VTR, or a portable 3/4" U-matic VCR . Typically, the two camera units would be carried by the camera operator, while a tape operator would carry the portable recorder. With the introduction of the RCA TK-76 in 1976, the Ikegami HL-77 in 1977, and the Sony BVP-300 in 1978, camera operators were finally able to carry on their shoulders
1526-710: A single-pixel border for over-scanning and dimensions . Test cards are as old as TV broadcasts, with documented use by the BBC in the United Kingdom in its early 30-line mechanical Baird transmissions from 1934 and later on as simplified "tuning signals" shown before startup as well as in Occupied France during World War II. They evolved to include gratings for resolution testing, grids to assist with picture geometry adjustments, and grayscale for brightness and contrast adjustments. For example, all these elements can be seen in
1635-521: A trailing period—as "mi", "M", "ml", and "m". The American National Institute of Standards and Technology now uses and recommends "mi" to avoid confusion with the SI metre (m) and millilitre (ml). However, derived units such as miles per hour or miles per gallon continue to be abbreviated as "mph" and "mpg" rather than "mi/h" and "mi/gal". In the United Kingdom, road signs use "m" as the abbreviation for mile though height and width restrictions also use "m" as
1744-405: A video picture signal on its own. The video signal was output to the studio for switching and transmission. By the fifties, electronic miniaturization had progressed to the point where some monochrome cameras could operate standalone and even be handheld. But the studio configuration remained, with the large cable bundle transmitting the signals back to the camera control unit (CCU). The CCU in turn
1853-635: Is U+3344 ㍄ SQUARE MAIRU , after マイル mairu . The international mile is precisely equal to 1.609 344 km (or 25146 / 15625 km as a fraction). It was established as part of the 1959 international yard and pound agreement reached by the United States, the United Kingdom, Canada, Australia, New Zealand, and the Union of South Africa , which resolved small but measurable differences that had arisen from separate physical standards each country had maintained for
1962-445: Is a facility for controlling the lens focus and zoom as well. These cameras are mounted on pan and tilt heads, and may be placed in a stationary position, such as atop a pole or tower, in a corner of a broadcast booth, or behind a basketball hoop. They can also be placed on robotic dollies, at the end of camera booms and cranes, or "flown" in a cable supported harness, as shown in the illustration. Lipstick cameras are so called because
2071-533: Is based upon the length of a meridian of latitude . The German geographical mile ( geographische Meile ) was previously 1 ⁄ 15 ° of latitude (7.4127 km). The informal term "metric mile" is used in some countries, in sports such as track and field athletics and speed skating , to denote a distance of 1,500 metres (0.932 miles). The 1500 meters is the premier middle distance running event in Olympic sports . In United States high-school competition,
2180-605: Is defined by the First International Extraordinary Hydrographic Conference in Monaco as exactly 1,852 metres (which is 1.151 miles or 6,076.12 feet). In the United States, the nautical mile was defined in the 19th century as 6,080.2 feet (1,853.24 m), whereas in the United Kingdom, the Admiralty nautical mile was defined as 6,080 feet (1,853.18 m) and was about one minute of latitude in
2289-474: Is designed for movies or scripted television to record files that are then color corrected during post-production . The video signal from a professional video camera can be broadcast live, or is meant to be edited quickly with little or no color or exposure adjustments needed. The earliest video cameras were mechanical flying-spot scanners which were in use in the 1920s and 1930s during the period of mechanical television . Improvements in video camera tubes in
SECTION 20
#17328768411272398-505: Is from Rome. The Italian mile ( miglio , pl. miglia ) was traditionally considered a direct continuation of the Roman mile, equal to 1000 paces, although its actual value over time or between regions could vary greatly. It was often used in international contexts from the Middle Ages into the 17th century and is thus also known as the "geographical mile", although
2507-406: Is normally possible with just a single video pickup. In both single sensor Bayer filter and triple sensor designs, the weak signal created by the sensors is amplified before being encoded into analog signals for use by the viewfinder and also encoded into digital signals for transmission and recording. The analog outputs were normally in the form of either a composite video signal, which combined
2616-436: Is used for the calibration of photocopiers . Photocopier test patterns are physical sheets that are photocopied, with the difference in the resulting photocopy revealing any tell-tale deviations or defects in the machine's ability to copy. There are also test patterns kits and software developed specifically for many consumer electronics. The B&K Television Analyst was developed in the 1960s for testing monochrome TV sets in
2725-398: Is used in radar -related subjects and is equal to 6,000 feet (1.8288 kilometres). The radar mile is a unit of time (in the same way that the light year is a unit of distance), equal to the time required for a radar pulse to travel a distance of two miles (one mile each way). Thus, the radar statute mile is 10.8 μs and the radar nautical mile is 12.4 μs. The geographical mile
2834-648: The Sjællandske miil , for instance, had been 11.13 km. The Germans also used a longer version of the geographical mile . The Breslau mile , used in Breslau , and from 1630 officially in all of Silesia , equal to 11,250 ells , or about 6,700 meters. The mile equaled the distance from the Piaskowa Gate all the way to Psie Pole ( Hundsfeld ). By rolling a circle with a radius of 5 ells through Piaskowa Island , Ostrów Tumski and suburban tracts, passing eight bridges on
2943-644: The 1593 Act of Parliament , which set it as a distance of 1,760 yards . Under American law , however, statute mile refers to the US survey mile. Foreign and historical units translated into English as miles usually employ a qualifier to describe the kind of mile being used but this may be omitted if it is obvious from the context, such as a discussion of the 2nd-century Antonine Itinerary describing its distances in terms of miles rather than Roman miles . The mile has been variously abbreviated in English—with and without
3052-599: The Chinese mile (now 500 m exactly). The Romans divided their mile into 5,000 pedēs ("feet") , but the greater importance of furlongs in the Elizabethan-era England meant that the statute mile was made equivalent to 8 furlongs or 5,280 feet in 1593. This form of the mile then spread across the British Empire , some successor states of which continue to employ the mile. The US Geological Survey now employs
3161-497: The Crystal Palace transmitter to test its new UHF network which it eventually launched as BBC Two in 1964. Test cards are also used in the broader context of video displays for concerts and live events. There are a variety of different test patterns, each testing a specific technical parameter: gradient monotone bars for testing brightness and color; a crosshatch pattern for aspect ratio , alignment, focus, and convergence; and
3270-456: The Exchequer , which thereafter verified local standards until its abolition in the 19th century. New brass standards are known to have been constructed under Henry VII and Elizabeth I . Arnold's c. 1500 Customs of London recorded a mile shorter than previous ones, coming to 0.947 international miles (5,000 feet) or 1.524 km. The English statute mile
3379-868: The Kyowa Sonic lens cleaning kits from 1997–2001, also included test patterns as well. More recent examples include the THX Optimizer which can be accessed in the setup menu in almost every THX-certified DVD, as well as well as the "HDR sRGB Graphics Test (400 nits)" and "Test Patterns" series available on Netflix meant to test out streaming bandwidth on Internet-enabled devices, especially on widescreen smart HDR TVs, 4K and 8K displays and also used to sync audio and video feeds, which can be affected, among other factors, by Bluetooth and Internet latency. Test patterns are also used to calibrate CCTV cameras and monitors, as well as medical imaging displays and equipment for telemedicine and diagnostic purposes, such as
Test card - Misplaced Pages Continue
3488-627: The SMPTE RP-133 medical diagnostic imaging test pattern specification for medical and surgical displays, created around 1983–86; as well as a later derivative called the TG18-QC test pattern created by the AAPM in 2001. Test patterns to calibrate X-ray machines , in particular those manufactured by Leeds Test Objects in England, also exist as well. Television has had such an impact in today's life that it has been
3597-623: The United Kingdom , and the United States , the financial imperatives of commercial television broadcasting mean that air-time is now typically filled with programmes and commercials (such as infomercials ) 24 hours a day, and non-commercial broadcasters have to match this. A late test card design, introduced in 2005 and fully adapted for HD, SD, 16:9 and 4:3 broadcasts, is defined on ITU-R Rec. BT.1729. It offers markings specificity design to test format conversions, chroma sampling, etc. Formerly
3706-455: The decempeda and dioptra then spread its use. In modern times, Agrippa's Imperial Roman mile was empirically estimated to have been about 1,618 yards (1,479 m; 4,854 ft; 0.919 mi) in length, slightly less than the 1,760 yards (1,609 m; 5,280 ft) of the modern international mile. In Hellenic areas of the Empire, the Roman mile ( Ancient Greek : μίλιον , mílion )
3815-409: The geographical mile is now a separate standard unit. The Arabic mile ( الميل , al-mīl ) was not the common Arabic unit of length ; instead, Arabs and Persians traditionally used the longer parasang or "Arabic league ". The Arabic mile was, however, used by medieval geographers and scientists and constituted a kind of precursor to the nautical or geographical mile . It extended
3924-446: The international mile and international foot . In the United States, the term statute mile formally refers to the survey mile, but for most purposes, the difference of less than 1 ⁄ 8 inch (3.2 mm) between the survey mile and the international mile (1609.344 metres exactly) is insignificant—one international mile is 0.999 998 US survey miles—so statute mile can be used for either. But in some cases, such as in
4033-533: The " ban mile" ( banska milja ), had been the Austrian mile given above. The Ottoman mile was 1,894.35 m (1.17709 mi), which was equal to 5,000 Ottoman foot. After 1933, the Ottoman mile was replaced with the modern Turkish mile (1,853.181 m). The CJK Compatibility Unicode block contains square-format versions of Japanese names for measurement units as written in katakana script. Among them, there
4142-471: The (temporary) transmitter and a replicating landscape feature causing ghosting . Said test cards were mainly transmitted from temporary mobile transmitters attached to caravan trailers based at the predicted locations of the ITA's eventual main transmitters, such as Croydon , Lichfield , Emley Moor and Winter Hill . Almost a decade later, the BBC started using a modified SMPTE monochrome test card radiating from
4251-474: The 10th century, the nominal prototype physical standard of English length was an arm-length iron bar (a yardstick) held by the king at Winchester ; the foot was then one-third of its length. Henry I was said to have made a new standard in 1101 based on his own arm. Following the issuance of Magna Carta in 1215, the barons of Parliament directed John and his son to keep the king 's standard measure ( Mensura Domini Regis ) and weight at
4360-430: The 1930s ushered in the era of electronic television . Earlier, cameras were very large devices, almost always in two sections. The camera section held the lens and camera tube pre-amplifiers and other necessary electronics, and was connected to a large diameter multicore cable to the remainder of the camera electronics, usually mounted in a separate room in the studio, or a remote truck. The camera head could not generate
4469-399: The 1980s and 1990s. Numerous novelty and collectible items has been patterned after the famous test card, including wall clocks, bedsheets, wristwatches, and clothing. The BBC Test Card F features throughout 2006-07 TV sci-fi detective series Life on Mars . In Britain, music rather than radio sound was usually played with the test card. The music played by the BBC, and afterwards ITV ,
Test card - Misplaced Pages Continue
4578-412: The 1980s, the test card was gradually seen less and less - it was pushed out first by Teletext pages, then extended programme hours. The same tapes were used to accompany both the test card and Ceefax on BBC channels, but some fans argue that new tapes introduced after Ceefax became the norm in 1983 were less musically interesting. Television camera A professional video camera (often called
4687-539: The 2000s, most professional video cameras are digital (instead of analog). The distinction between professional video cameras and movie cameras narrowed as HD digital video cameras with sensors the same size as 35mm movie cameras - plus dynamic range ( exposure latitude ) and color rendition approaching film quality - were introduced in the late 2010s. Nowadays, HDTV cameras designed for broadcast television, news, sports, events and other works such as reality TV are termed as professional video cameras. A digital movie camera
4796-429: The BBC began to build up its own library of specially produced music for the half hour tapes – initially three tunes in similar style, followed by an identification sign (the three notes B-B-C played on celesta ). ITV (which began its first trade transmissions in 1957) continued to use commercially available recordings until the late 1960s, when it also began to make specially produced tapes. For rights reasons, much of
4905-624: The NAD27, is defined in metres. State Plane Coordinate Systems were then updated, but the National Geodetic Survey left individual states to decide which (if any) definition of the foot they would use. All State Plane Coordinate Systems are defined in metres, and 42 of the 50 states only use the metre-based State Plane Coordinate Systems. However, eight states also have State Plane Coordinate Systems defined in feet, seven of them in US survey feet and one in international feet. State legislation in
5014-493: The NTSC standard and was later modified for European and Australian PAL standards. Among other uses, it consisted of a flying spot scanner on which a test pattern printed on a cellulose acetate slide was shown. When CRT monitors were still commonly used on personal computers , specific test patterns were created for proper calibration of such monitors in the cases whereby multimedia images could not be shown properly on said monitors. Some VCD and DVD lens cleaner discs, such as
5123-456: The Roman computations of the mile as 5,000 feet, 1,000 paces , or 8 longer divisions, which they equated with their " furrow 's length" or furlong . The origins of English units are "extremely vague and uncertain", but seem to have been a combination of the Roman system with native British and Germanic systems both derived from multiples of the barleycorn . Probably by the reign of Edgar in
5232-528: The Roman mile is the milestone . All roads radiated out from the Roman Forum throughout the Empire – 50,000 (Roman) miles of stone-paved roads. At every mile was placed a shaped stone. Originally, these were obelisks made from granite, marble, or whatever local stone was available. On these was carved a Roman numeral , indicating the number of miles from the centre of Rome – the Forum. Hence, one can know how far one
5341-410: The Roman mile of one thousand paces . The present international mile is usually what is understood by the unqualified term mile . When this distance needs to be distinguished from the nautical mile, the international mile may also be described as a land mile or statute mile. In British English , statute mile may refer to the present international mile or to any other form of English mile since
5450-615: The Roman mile to fit an astronomical approximation of 1 arcminute of latitude measured directly north-and-south along a meridian . Although the precise value of the approximation remains disputed, it was somewhere between 1.8 and 2.0 km. The " old English mile " of the medieval and early modern periods varied but seems to have measured about 1.3 international miles (2.1 km). The old English mile varied over time and location within England. The old English mile has also been defined as 79,200 or 79,320 inches (1.25 or 1.2519 statute miles). The English long continued
5559-493: The US State Plane Coordinate Systems (SPCSs), which can stretch over hundreds of miles, the accumulated difference can be significant, so it is important to note that the reference is to the US survey mile. The United States redefined its yard in 1893, and this resulted in US and Imperial measures of distance having very slightly different lengths. The North American Datum of 1983 (NAD83), which replaced
SECTION 50
#17328768411275668-550: The US Virgin Islands. The mile is even encountered in Canada, though this is predominantly in rail transport and horse racing, as the roadways have been metricated since 1977. Ireland gradually replaced miles with kilometres, including in speed measurements; the process was completed in 2005. The US survey mile is 5,280 US survey feet , or 1,609.347 metres and 0.30480061 metres respectively. Both are very slightly longer than
5777-451: The US is important for determining which conversion factor from the metric datum is to be used for land surveying and real estate transactions, even though the difference (2 ppm ) is hardly significant, given the precision of normal surveying measurements over short distances (usually much less than a mile). Twenty-four states have legislated that surveying measures be based on the US survey foot, eight have legislated that they be based on
5886-461: The US survey foot and US survey mile, as permitted by their 1959 decision, with effect on January 1, 2023. The nautical mile was originally defined as one minute of arc along a meridian of the Earth. Navigators use dividers to step off the distance between two points on the navigational chart, then place the open dividers against the minutes-of-latitude scale at the edge of the chart, and read off
5995-475: The United Kingdom, the United States, and a number of countries with fewer than one million inhabitants, most of which are UK or US territories or have close historical ties with the UK or US. The modern English word mile derives from Middle English myle and Old English mīl , which was cognate with all other Germanic terms for miles . These derived from the nominal ellipsis form of mīlle passus 'mile' or mīlia passuum 'miles',
6104-459: The United States by an international agreement in 1959 , when it was formally redefined with respect to SI units as exactly 1,609.344 metres . With qualifiers, mile is also used to describe or translate a wide range of units derived from or roughly equivalent to the Roman mile (roughly 1.48 km ), such as the nautical mile (now 1.852 km exactly), the Italian mile (roughly 1.852 km ), and
6213-525: The additional studio accessories. In the late 1990s, as HDTV broadcasting commenced, HDTV cameras suitable for news and general purpose work were introduced. Though they delivered much better image quality, their overall operation was identical to their standard definition predecessors. New methods of recording for cameras were introduced to supplant video tape , tapeless cameras. Ikegami and Avid introduced EditCam in 1996, based on interchangeable hard drives . Panasonic introduced P2 cameras. These recorded
6322-460: The camera is mounted in place. Mile The mile , sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of length; both are based on the older English unit of length equal to 5,280 English feet , or 1,760 yards . The statute mile was standardised between the Commonwealth of Nations and
6431-448: The color and luminance information to a single output; or an R-Y B-Y Y component video output through three separate connectors. Most television studio cameras stand on the floor , usually with pneumatic or hydraulic mechanisms called pedestals to adjust the height and position in the studio. The cameras in a multiple-camera setup are controlled by a device known as a camera control unit (CCU), to which they are connected via
6540-401: The colour or resolution of their tube counterparts, but the benefits of CCD technology, such as introducing smaller and lightweight cameras, a better and more stable image (that was not prone to image burn in or lag) and no need for registration meant development on CCD imagers quickly took off and, once rivaling and offering a superior image to a tube sensor, began displacing tube-based cameras -
6649-616: The definition of the foot in the Mendenhall Order of 1893, with 1 foot = 1200 / 3937 (≈0.304800609601) metres and the definition was retained for data derived from NAD27, but renamed the US survey foot to distinguish it from the international foot. Thus a survey mile = 1200 / 3937 × 5280 (≈1609.347218694) metres. An international mile = 1609.344 / ( 1200 / 3937 × 5280) (=0.999998) survey miles. The exact length of
SECTION 60
#17328768411276758-502: The digital professional video cameras. These cameras used CCD sensors and recorded video digitally on flash storage . These were followed by digital HDTV cameras. As digital technology improved and also due to digital television transition , digital professional video cameras have become dominant in television studios, ENG, EFP and even in other areas since 2010s. CCD sensors were eventually replaced by CMOS sensors . Most professional cameras utilize an optical prism block directly behind
6867-509: The discrepancy with latitude measurement to less than 2%). The metric system was introduced in the Netherlands in 1816, and the metric mile became a synonym for the kilometre, being exactly 1,000 m. Since 1870, the term mijl was replaced by the equivalent kilometer . Today, the word mijl is no longer used, except as part of certain proverbs and compound terms like mijlenver ("miles away"). The German mile ( Meile )
6976-452: The distance in nautical miles. The Earth is not perfectly spherical but an oblate spheroid , so the length of a minute of latitude increases by 1% from the equator to the poles, as seen for example in the WGS84 ellipsoid , with 1,843 metres (6,046 ft) at the equator, 1,862 metres (6,108 ft) at the poles and average 1,852 metres (6,076 ft). Since 1929 the international nautical mile
7085-452: The downstream signal path, were introduced in the late-1960s, and became commonly used from the 1970s and 80s. These are generated by test signal generators , which do not depend on the correct configuration (and presence) of a camera, and can also test for additional parameters such as correct color decoding, sync , frames per second , and frequency response. These patterns are specially tailored to be used in conjunction with devices such as
7194-523: The early 1970s - the first generation of cameras were split into a camera head unit (the body of the camera, containing the lens and pickup tubes, and held on the shoulder or a body brace in front of the operator) connected via a cable bundle to a backpack CCU. The Ikegami HL-33, the RCA TKP45 and the Thomson Microcam were portable two piece color cameras introduced in the early 1970s. For field work
7303-671: The international foot, and eighteen have not specified which conversion factor to use. SPCS 83 legislation refers to state legislation that has been passed or updated using the newer 1983 NAD data. Most states have done so. Two states, Alaska and Missouri , and two jurisdictions, Guam and Puerto Rico , do not specify which foot to use. Two states, Alabama and Hawaii , and four jurisdictions, Washington, DC , US Virgin Islands , American Samoa and Northern Mariana Islands , do not have SPCS 83 legislation. In October 2019, US National Geodetic Survey and National Institute of Standards and Technology announced their joint intent to retire
7412-429: The land mile varied slightly among English-speaking countries until the international yard and pound agreement in 1959 established the yard as exactly 0.9144 metres, giving a mile of exactly 1,609.344 metres. The US adopted this international mile for most purposes, but retained the pre-1959 mile for some land-survey data, terming it the U. S. survey mile . In the United States, statute mile normally refers to
7521-459: The large, very long focal length zoom lenses made for studio camera mounting. These cameras have no recording ability on their own, and transmit their signals back to the broadcast truck through a fiber optic, triax , radio frequency or the virtually obsolete multicore cable. Remote cameras are typically very small camera heads designed to be operated by remote control. Despite their small size, they are often capable of performance close to that of
7630-413: The larger ENG and EFP types. Block cameras are so called because the camera head is a small block, often smaller than the lens itself. Some block cameras are completely self-contained, while others only contain the sensor block and its pre-amps, thus requiring connection to a separate camera control unit in order to operate. All the functions of the camera can be controlled from a distance, and often there
7739-412: The latitudes of the south of the UK. Other nations had different definitions of the nautical mile. The nautical mile per hour is known as the knot . Nautical miles and knots are almost universally used for aeronautical and maritime navigation, because of their relationship with degrees and minutes of latitude and the convenience of using the latitude scale on a map for distance measuring. The data mile
7848-545: The latter of which were all but disused by the early 1990s. Eventually, cameras with the recorder permanently mated to the camera head became the norm for ENG. In studio cameras, the camera electronics shrank, and CCD imagers replaced the pickup tubes. The thick multi-core cables connecting the camera head to the CCU were replaced in the late seventies with triax connections, a slender video cable that carried multiple video signals, intercom audio, and control circuits, and could be run for
7957-550: The length of an ell was not standardised, so that the length of a mile could range between 3,280 m and 4,280 m. In the sixteenth, the Dutch had three different miles: small ( kleine ), medium ( middelbaar/gemeen ), and large ( groote ). The Dutch kleine mile had the historical definition of one hour's walking ( uur gaans ), which was defined as 24 stadia, 3000 paces, or 15,000 Amsterdam or Rhineland feet (respectively 4,250 m or 4,710 m). The common Dutch mile
8066-517: The length of the rod by 1 ⁄ 11 would have amounted to a significant tax increase. Parliament instead opted to maintain the mile of 8 furlongs (which were derived from the rod) and to increase the number of feet per mile from the old Roman value. The applicable passage of the statute reads: "A Mile shall contain eight Furlongs, every Furlong forty Poles, and every Pole shall contain sixteen Foot and an half." The statute mile therefore contained 5,280 feet or 1,760 yards. The distance
8175-412: The lens and sensor block combined are similar in size and appearance to a lipstick container. These are either hard mounted in a small location, such as a race car, or on the end of a boom pole. The sensor block and lens are separated from the rest of the camera electronics by a long thin multi conductor cable. The camera settings are manipulated from this box, while the lens settings are normally set when
8284-418: The lens. This prism block (a trichroic assembly comprising two dichroic prisms ) separates the image into the three primary colors , red, green, and blue, directing each color into a separate charge-coupled device (CCD) or Active pixel sensor (CMOS image sensor) mounted to the face of each prism. Some high-end consumer cameras also do this, producing a higher-resolution image, with better color fidelity than
8393-533: The main motif for numerous collectors' coins and medals. One of the most recent examples is The 50 Years of Television commemorative coin minted on 9 March 2005, in Austria . The obverse of the coin shows the centre portion of the Telefunken T05 test card, while the reverse shows several milestones in the history of television. The Philips Pattern is widely recognised as one of the iconic popular culture symbols of
8502-488: The metre for official purposes, but legacy data from its 1927 geodetic datum has meant that a separate US survey mile ( 6336 / 3937 km) continues to see some use, although it was officially phased out in 2022. While most countries replaced the mile with the kilometre when switching to the International System of Units (SI), the international mile continues to be used in some countries, such as
8611-419: The mile was changed as with improved calculations of the circumference of the Earth. In 1617, Willebrord Snellius calculated a degree of the circumference of the Earth at 28,500 Rijnlantsche Roeden (within 3.5% of the actual value), which resulted in a Dutch mile of 1900 rods. By the mid-seventeenth century, map scales assigned 2000 rods to the common Dutch mile, which equalled around 7,535 m (reducing
8720-407: The model of the tripod). Initial models used analog technology, but are now obsolete, supplanted by digital models. Studio cameras are light and small enough to be taken off the pedestal and the lens changed to a smaller size to be used handheld on a camera operator's shoulder, but they still have no recorder of their own and are cable-bound. Cameras can also be mounted on a tripod , a dolly or
8829-666: The most accepted equivalencies are 1,976 Imperial yards (1.123 statute miles or 1.81 km). It was legally abolished three times: first by a 1685 act of the Scottish Parliament , again by the 1707 Treaty of Union with England, and finally by the Weights and Measures Act 1824 . It had continued in use as a customary unit through the 18th century but had become obsolete by its final abolition. The Irish mile ( míle or míle Gaelach ) measured 2,240 yards: approximately 1.27 statute miles or 2.048 kilometres. It
8938-642: The music was recorded by light music orchestras in France and Germany, though sometimes by British musicians, or top international session players using pseudonyms, such as The Oscar Brandenburg Orchestra (an amalgamation of Neil Richardson , Alan Moorhouse and Johnny Pearson ) or the Stuttgart Studio Orchestra. Other composers and bandleaders commissioned for this type of work included Gordon Langford , Ernest Tomlinson . Roger Roger , Heinz Kiessling , Werner Tautz, Frank Chacksfield and Syd Dale . During
9047-460: The negative excursions of the colorburst signal may go below 0 IRE). Between the color bars and proper adjustment of brightness and contrast controls to the limits of perception of the first sub-black bar, an analog receiver (or other equipment such as VTRs) can be adjusted to provide impressive fidelity. Test cards have also been used to determine actual coverage contours for new television broadcasting antennas and/or networks. In preparation for
9156-566: The new commercial ITV service in the 1950s, the Independent Television Authority (ITA) tasked Belling & Lee, an Enfield -based British electronics company best known for inventing the Belling-Lee connector just over three decades earlier, with designing a series of Pilot Test Transmission test cards and slides intended for potential viewers and DX-enthusiasts to test the ITA's new Band III VHF transmitter network that
9265-616: The previous standards was 2 ppm , or about 3.2 millimetres ( 1 ⁄ 8 inch) per mile. The US standard was slightly longer and the old Imperial standards had been slightly shorter than the international mile. When the international mile was introduced in English-speaking countries, the basic geodetic datum in America was the North American Datum of 1927 (NAD27). This had been constructed by triangulation based on
9374-430: The quick completion of news stories, compared to the need to chemically process film before it could be shown or edited. However some news feature stories for weekly news magazine shows continued to use 16mm film cameras until the 1990s. At first all these cameras used tube-based sensors, but charge-coupled device (CCD) imagers came on the scene in the mid-80s, bringing numerous benefits. Early CCD cameras could not match
9483-416: The smaller consumer camcorder , they differ in several regards: Electronic field production cameras are similar to studio cameras in that they are used primarily in multiple camera switched configurations, but outside the studio environment, for concerts, sports and live news coverage of special events. These versatile cameras can be carried on the shoulder, or mounted on camera pedestals and cranes, with
9592-402: The specific size and shape of the setup in question. These custom test images can also be an opportunity for the technicians to hide inside jokes for the crew to see while installing equipment for a show. Rather than physical test cards, which had to be televised using a camera, television stations often used a special purpose camera tube which had the test pattern painted on the inside screen of
9701-413: The survey mile, about 3.219 mm ( 1 ⁄ 8 inch) longer than the international mile (the international mile is exactly 0.0002% less than the US survey mile). While most countries abandoned the mile when switching to the metric system , the international mile continues to be used in some countries, such as Liberia , Myanmar , the United Kingdom and the United States. It is also used in
9810-443: The symbol for the metre, which may be displayed alongside feet and inches. The BBC style holds that "there is no acceptable abbreviation for 'miles ' " and so it should be spelled out when used in describing areas. The Roman mile ( mille passus , lit. "thousand paces"; abbr. m.p. ; also milia passuum and mille ) consisted of a thousand paces as measured by every other step—as in
9919-401: The target, rather than displaying an image, a varying electrical signal was produced generating a video signal from the etched pattern. Monoscope tubes had the advantage over test cards that a full TV camera was not needed, and the image was always properly framed and in focus. They fell out of use after the 1960s as they were not able to produce color images. A lesser-known kind of test pattern
10028-487: The term is sometimes used for a race of 1,600 metres (0.994 miles). The Scandinavian mile ( mil ) remains in common use in Norway and Sweden, where it has meant precisely 10 km since metrication in 1889. It is used in informal situations and in measurements of fuel consumption, which are often given as litres per mil . In formal situations (such as official road signs) only kilometres are given. The Swedish mile
10137-458: The total distance of the left foot hitting the ground 1,000 times. When Roman legionaries were well-fed and harshly driven in good weather, they thus created longer miles. The distance was indirectly standardised by Agrippa 's establishment of a standard Roman foot (Agrippa's own) in 29 BC , and the definition of a pace as 5 feet. An Imperial Roman mile thus denoted 5,000 Roman feet . Surveyors and specialised equipment such as
10246-399: The tube. Each tube was only capable of generating the one test image, hence it was called a monoscope . Monoscopes were similar in construction to an ordinary cathode-ray tube (CRT), only instead of displaying an image on its screen it scanned a built-in image. The monoscope contained a formed metal target in place of the phosphor coating at its "screen" end and as the electron beam scanned
10355-423: The use of test cards has also expanded beyond television to other digital displays such as large LED walls and video projectors . Test cards typically contain a set of patterns to enable television cameras and receivers to be adjusted to show the picture correctly (see SMPTE color bars ). Most modern test cards include a set of calibrated color bars which will produce a characteristic pattern of "dot landings" on
10464-599: The way, the standard Breslau mile was determined. The Saxon post mile ( kursächsische Postmeile or Polizeimeile , introduced on occasion of a survey of the Saxon roads in the 1700s, corresponded to 2,000 Dresden rods , equivalent to 9.062 kilometres. The Hungarian mile ( mérföld or magyar mérföld ) varied from 8.3790 km to 8.9374 km before being standardised as 8.3536 km. The Portuguese mile ( milha ) used in Portugal and Brazil
10573-656: The yard. As with the earlier statute mile , it continues to comprise 1,760 yards or 5,280 feet. The old Imperial value of the yard was used in converting measurements to metric values in India in a 1976 Act of the Indian Parliament. However, the current National Topographic Database of the Survey of India is based on the metric WGS-84 datum , which is also used by the Global Positioning System . The difference from
10682-427: Was library music , which was licensed on more favourable terms for frequent use than commercially available alternatives. Later, Channel 4 used UK library LPs from publishers like KPM , Joseph Weinberger and Ready Music. Until September 1955, the BBC used live playing 78 RPM commercial records as an audio background to the test cards. After that date, they switched to using recorded music on tape. The following year,
10791-485: Was 2.0873 km prior to metrication. The Russian mile ( миля or русская миля , russkaya milya ) was 7.468 km, divided into 7 versts . The Croatian mile ( hrvatska milja ), first devised by the Jesuit Stjepan Glavač on a 1673 map, is the length of an arc of the equator subtended by 1 / 10 ° or 11.13 km exactly. The previous Croatian mile, now known as
10900-666: Was 24,000 German feet. The standardised Austrian mile used in southern Germany and the Austrian Empire was 7.586 km; the Prussian mile used in northern Germany was 7.5325 km. Following its standardisation by Ole Rømer in the late 17th century, the Danish mile ( mil ) was precisely equal to the Prussian mile and likewise divided into 24,000 feet. These were sometimes treated as equivalent to 7.5 km. Earlier values had varied:
11009-410: Was 32 stadia, 4,000 paces, or 20,000 feet (5,660 m or 6,280 m). The large mile was defined as 5000 paces. The common Dutch mile was preferred by mariners, equating with 15 to one degree of latitude or one degree of longitude on the equator . This was originally based upon Ptolemy 's underestimate of the Earth's circumference. The ratio of 15 Dutch miles to a degree remained fixed while the length of
11118-553: Was designed with the assistance of the General Post Office (GPO), then the UK's government-run PTT agency . These test cards, some featuring the G9AED call sign assigned by the GPO for said transmissions, featured a squiggly line in a circle in the middle of the test card with an on-screen line gauge indicated in miles which was used as a guide to reveal the distance between the receiver,
11227-468: Was established by a Weights and Measures Act of Parliament in 1593 during the reign of Queen Elizabeth I . The act on the Composition of Yards and Perches had shortened the length of the foot and its associated measures, causing the two methods of determining the mile to diverge. Owing to the importance of the surveyor's rod in deeds and surveying undertaken under Henry VIII , decreasing
11336-439: Was not uniformly adopted. Robert Morden had multiple scales on his 17th-century maps which included continuing local values: his map of Hampshire , for example, bore two different "miles" with a ratio of 1 : 1.23 and his map of Dorset had three scales with a ratio of 1 : 1.23 : 1.41 . In both cases, the traditional local units remained longer than the statute mile. The English statute mile
11445-660: Was said to have been codified under Dyfnwal the Bald and Silent and retained unchanged by Hywel the Good . Along with other Welsh units, it was discontinued following the conquest of Wales by Edward I of England in the 13th century. The Scots mile was longer than the English mile, as mentioned by Robert Burns in the first verse of his poem " Tam o' Shanter ". It comprised 8 (Scots) furlongs divided into 320 falls or faws (Scots rods ). It varied from place to place but
11554-443: Was superseded in 1959 by the international mile by international agreement. The Welsh mile ( milltir or milldir ) was 3 statute miles and 1,470 yards long (6.17 km). It comprised 9,000 paces ( cam ), each of 3 Welsh feet ( troedfedd ) of 9 inches ( modfeddi ). (The Welsh inch is usually reckoned as equivalent to the English inch.) Along with other Welsh units , it
11663-577: Was used beside the native Greek units as equivalent to 8 stadia of 600 Greek feet . The mílion continued to be used as a Byzantine unit and was also used as the name of the zero mile marker for the Byzantine Empire , the Milion , located at the head of the Mese near Hagia Sophia . The Roman mile spread throughout Europe, with its local variations giving rise to the different units. Also arising from
11772-463: Was used in Ireland from the 16th century plantations until the 19th century, with residual use into the 20th century. The units were based on " English measure " but used a linear perch measuring 7 yards (6.4 m) as opposed to the English rod of 5.5 yards (5.0 m). The Dutch mile ( mijl ) has had different definitions throughout history. One of the older definitions was 5,600 ells . But
11881-506: Was used to align and operate the camera's functions, such as exposure, system timing, video and black levels . The first color cameras (1950s in the US, early 1960s in Europe), notably the RCA TK-40/41 series, were much more complex with their three (and in some models four) pickup tubes, and their size and weight drastically increased. Handheld color cameras did not come into general use until
#126873