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LENS SPEED [9 records]
Record 1 - internal organization data 2015-04-08
Record 1, English
Record 1, Subject field(s)
- Optical Glass
- Photography
Record 1, Main entry term, English
- mirror lens
1, record 1, English, mirror%20lens
correct
Record 1, Abbreviations, English
Record 1, Synonyms, English
- catadioptric lens 1, record 1, English, catadioptric%20lens
correct
Record 1, Textual support, English
Record number: 1, Textual support number: 1 CONT
Mirror lenses have no diaphragm; light transmission is regulated by filters built into the rear of the lens, or by varying the shutter speed. Because of its reflecting design and the different types of mirrored surfaces used to transmit the light, most mirror lenses will transmit up to a full f-stop less light to the film plane than their rated speed. 1, record 1, English, - mirror%20lens
Record 1, French
Record 1, Domaine(s)
- Verres d'optique
- Photographie
Record 1, Main entry term, French
- objectif catadioptrique
1, record 1, French, objectif%20catadioptrique
correct, masculine noun
Record 1, Abbreviations, French
Record 1, Synonyms, French
- objectif à miroir 2, record 1, French, objectif%20%C3%A0%20miroir
correct, masculine noun
Record 1, Textual support, French
Record number: 1, Textual support number: 1 CONT
L'objectif catadioptrique [...] consiste essentiellement en une combinaison de lentilles et de miroirs d'où la lumière est projetée par réfraction d'une lentille sur un réflecteur interne, pour être ensuite projetée vers le plan focal, selon une espèce de trajectoire que l'on pourrait décrire comme étant en forme de zigzag. 1, record 1, French, - objectif%20catadioptrique
Record number: 1, Textual support number: 2 CONT
L'un des désavantages (typiques) des objectifs catadioptriques est l'absence de diaphragme. 1, record 1, French, - objectif%20catadioptrique
Record 1, Spanish
Record 1, Textual support, Spanish
Record 2 - internal organization data 2009-07-16
Record 2, English
Record 2, Subject field(s)
- Signalling (Rail Transport)
- Railroad Safety
Record 2, Main entry term, English
- four-aspect signal
1, record 2, English, four%2Daspect%20signal
correct
Record 2, Abbreviations, English
Record 2, Synonyms, English
- four aspect signal 2, record 2, English, four%20aspect%20signal
correct
Record 2, Textual support, English
Record number: 2, Textual support number: 1 CONT
The most common type of four-aspect signal has four lenses arranged from top to bottom as follows : yellow, green, yellow, red. Modern LED [light-emitting diode] signals with just two lenses can show all four aspects. The lower lens is capable of displaying a red, yellow or green light. Not all lines use four-aspect signalling-three or two aspects are used where the headway and line speed allow. 1, record 2, English, - four%2Daspect%20signal
Record 2, French
Record 2, Domaine(s)
- Signalisation (Transport par rail)
- Sécurité (Transport par rail)
Record 2, Main entry term, French
- bloc à quatre aspects
1, record 2, French, bloc%20%C3%A0%20quatre%20aspects
masculine noun
Record 2, Abbreviations, French
Record 2, Synonyms, French
Record 2, Textual support, French
Record 2, Spanish
Record 2, Textual support, Spanish
Record 3 - internal organization data 2008-01-14
Record 3, English
Record 3, Subject field(s)
- Photography
Record 3, Main entry term, English
- periphery camera system
1, record 3, English, periphery%20camera%20system
correct
Record 3, Abbreviations, English
Record 3, Synonyms, English
- periphotographic system 2, record 3, English, periphotographic%20system
correct
Record 3, Textual support, English
Record number: 3, Textual support number: 1 CONT
An improvement over the first "panoramic" system involved eliminating the rotation of the photographic apparatus, and instead disposing the object to be photographed in front of the objective lens and rotating the object itself. As in a "panoramic" system, the image of the object is recorded on a photographic film which is moved linearly at the same speed as the speed of rotation of the object. Such a system is known as a "periphotographic system". 2, record 3, English, - periphery%20camera%20system
Record 3, French
Record 3, Domaine(s)
- Photographie
Record 3, Main entry term, French
- banc périphotographique
1, record 3, French, banc%20p%C3%A9riphotographique
correct, masculine noun
Record 3, Abbreviations, French
Record 3, Synonyms, French
Record 3, Textual support, French
Record number: 3, Textual support number: 1 DEF
[Système qui] permet de reproduire sur un plan, avec n'importe quel appareil photographique, l'image de toute la surface latérale d'un objet de forme de révolution. 2, record 3, French, - banc%20p%C3%A9riphotographique
Record number: 3, Textual support number: 1 OBS
[Le banc périphotographique] permet, à partir d'une motorisation, de transmettre le mouvement de rotation au plateau qui supporte l'appareil photographique. 2, record 3, French, - banc%20p%C3%A9riphotographique
Record number: 3, Textual support number: 2 OBS
Le banc périphotographique [...] pourra en effet servir non seulement à étudier les vases antiques mais aussi tout autre objet approximativement cylindrique. 3, record 3, French, - banc%20p%C3%A9riphotographique
Record 3, Spanish
Record 3, Textual support, Spanish
Record 4 - internal organization data 2005-11-02
Record 4, English
Record 4, Subject field(s)
- Photography
Record 4, Main entry term, English
- dedicated flash
1, record 4, English, dedicated%20flash
correct
Record 4, Abbreviations, English
Record 4, Synonyms, English
Record 4, Textual support, English
Record number: 4, Textual support number: 1 DEF
A fully automatic flash that works only with specific cameras. 1, record 4, English, - dedicated%20flash
Record number: 4, Textual support number: 1 CONT
Dedicated flash units automatically set the proper flash synchronization speed and lens aperture, and electronic sensors within the camera automatically control exposure by regulating the amount of light from the flash. 2, record 4, English, - dedicated%20flash
Record 4, French
Record 4, Domaine(s)
- Photographie
Record 4, Main entry term, French
- flash dédié
1, record 4, French, flash%20d%C3%A9di%C3%A9
correct, masculine noun
Record 4, Abbreviations, French
Record 4, Synonyms, French
Record 4, Textual support, French
Record number: 4, Textual support number: 1 DEF
Flash automatique conçu pour fonctionner avec certaines marques d'appareils photo. 2, record 4, French, - flash%20d%C3%A9di%C3%A9
Record number: 4, Textual support number: 1 CONT
Le flash dédié permet de sélectionner automatiquement la vitesse de synchronisation flash appropriée et l'ouverture de l'objectif tout en contrôlant automatiquement l'exposition grâce à des capteurs intégrés dans l'appareil photo qui règlent la quantité de lumière émise par le flash. 2, record 4, French, - flash%20d%C3%A9di%C3%A9
Record number: 4, Textual support number: 1 OBS
Pluriel : des flashs ou des flashes. 3, record 4, French, - flash%20d%C3%A9di%C3%A9
Record number: 4, Textual support number: 2 OBS
flashs (pl.) : Cette graphie, puisée des Rectifications de l'orthographe recommandées par le Conseil supérieur de la langue française, est attestée dans le Petit Robert (2004). 4, record 4, French, - flash%20d%C3%A9di%C3%A9
Record 4, Spanish
Record 4, Textual support, Spanish
Record 5 - internal organization data 2004-09-09
Record 5, English
Record 5, Subject field(s)
- Photography
Record 5, Main entry term, English
- stopped down metering
1, record 5, English, stopped%20down%20metering
correct
Record 5, Abbreviations, English
Record 5, Synonyms, English
- stopped-down metering 2, record 5, English, stopped%2Ddown%20metering
correct
- working aperture metering 3, record 5, English, working%20aperture%20metering
Record 5, Textual support, English
Record number: 5, Textual support number: 1 DEF
Reading the light metering through the camera lens with the aperture set at the position that it’ll be at when the photo is taken. 4, record 5, English, - stopped%20down%20metering
Record number: 5, Textual support number: 1 CONT
Fortunately, you can still meter using the stopped-down metering approach on most cameras. By pressing a depth-of-field button, the camera is placed into stopped-down metering mode too. The lens is stopped down to the taking aperture automatically on some adapters. On T-mount and other purely mechanical mounts, you may have to turn the aperture ring to the desired taking aperture. In either case, the camera is now metering at the actual stopped down aperture. You can set the shutter speed and aperture as desired, based on your meter reading. 2, record 5, English, - stopped%20down%20metering
Record 5, French
Record 5, Domaine(s)
- Photographie
Record 5, Main entry term, French
- mesure ouverture utile
1, record 5, French, mesure%20ouverture%20utile
proposal, feminine noun
Record 5, Abbreviations, French
Record 5, Synonyms, French
- mesure ouverture pondérée 1, record 5, French, mesure%20ouverture%20pond%C3%A9r%C3%A9e
proposal, feminine noun
Record 5, Textual support, French
Record number: 5, Textual support number: 1 OBS
[...] si, face à une source lumineuse, on applique à l'arrière de l'objectif un verre dépoli, il se forme sur ce dernier un cercle lumineux dont le diamètre est l'ouverture utile dite aussi ouverture mécanique. 2, record 5, French, - mesure%20ouverture%20utile
Record 5, Spanish
Record 5, Textual support, Spanish
Record 6 - internal organization data 2004-05-26
Record 6, English
Record 6, Subject field(s)
- Audiovisual Techniques and Equipment
- Photography
Record 6, Main entry term, English
- lens stop
1, record 6, English, lens%20stop
correct
Record 6, Abbreviations, English
Record 6, Synonyms, English
- diaphragm setting 2, record 6, English, diaphragm%20setting
correct
Record 6, Textual support, English
Record number: 6, Textual support number: 1 DEF
[A setting on] a variable iris diaphragm. 1, record 6, English, - lens%20stop
Record number: 6, Textual support number: 1 CONT
Fixed focus 70mm lens in single speed shutter. 2 diaphragm settings(BW f16 and Color f11). Hot shoe on top. 3, record 6, English, - lens%20stop
Record 6, French
Record 6, Domaine(s)
- Audiovisuel (techniques et équipement)
- Photographie
Record 6, Main entry term, French
- cran de diaphragme
1, record 6, French, cran%20de%20diaphragme
correct, masculine noun
Record 6, Abbreviations, French
Record 6, Synonyms, French
Record 6, Textual support, French
Record number: 6, Textual support number: 1 OBS
cran : Quand on tourne la bague de réglage du diaphragme sur un appareil photo ou sur l'agrandisseur. «Ouvrir» ou «fermer d'un cran» revient donc à passer d'une valeur entière la plus proche, ce qui divise ou multiplie par 2 la quantité de lumière admise. 1, record 6, French, - cran%20de%20diaphragme
Record 6, Spanish
Record 6, Textual support, Spanish
Record 7 - internal organization data 2004-05-10
Record 7, English
Record 7, Subject field(s)
- Optics
- Photography
Record 7, Main entry term, English
- lens speed
1, record 7, English, lens%20speed
correct
Record 7, Abbreviations, English
Record 7, Synonyms, English
Record 7, Textual support, English
Record number: 7, Textual support number: 1 DEF
The largest lens opening [smallest f-number] at which a lens can be set. 2, record 7, English, - lens%20speed
Record number: 7, Textual support number: 1 CONT
Lens speed is determined by the maximum aperture of the lens(the largest lens opening or the smallest f-number) in relation to it's focal length. The "speed" of a lens is relative, a 400 mm lens with a maximum aperture of f/3. 5 is considered extremely fast, while a 28mm f/3. 5 lens is thought to be relatively slow. 3, record 7, English, - lens%20speed
Record number: 7, Textual support number: 1 OBS
A "fast" lens transmits more light and has a larger opening than a "slow" lens. 2, record 7, English, - lens%20speed
Record 7, Key term(s)
- speed of a lens
Record 7, French
Record 7, Domaine(s)
- Optique
- Photographie
Record 7, Main entry term, French
- clarté d'un objectif
1, record 7, French, clart%C3%A9%20d%27un%20objectif
correct, feminine noun
Record 7, Abbreviations, French
Record 7, Synonyms, French
- rapidité d'un objectif 2, record 7, French, rapidit%C3%A9%20d%27un%20objectif
feminine noun
- luminosité d'un objectif 2, record 7, French, luminosit%C3%A9%20d%27un%20objectif
feminine noun
Record 7, Textual support, French
Record number: 7, Textual support number: 1 DEF
La plus grande ouverture [...] sur laquelle on peut régler l'objectif grâce au diaphragme. 1, record 7, French, - clart%C3%A9%20d%27un%20objectif
Record number: 7, Textual support number: 1 OBS
Un objectif «clair» transmet plus de lumière et a une ouverture plus grande qu'un objectif de petite ouverture. 1, record 7, French, - clart%C3%A9%20d%27un%20objectif
Record number: 7, Textual support number: 2 OBS
Caractéristiques d'un objectif. [...] Sa luminosité. C'est sa capacité à absorber et restituer la luminosité de votre scène. La luminosité ou ouverture se caractérise par le sigle «f» et un chiffre, plus le chiffre est petit (ex : 1.4 ou 1.8) plus votre objectif est lumineux. Plus un objectif est lumineux plus il autorise des vitesses élevées, une profondeur de champs restreinte donc de très jolis flous et plus son prix augmente. 2, record 7, French, - clart%C3%A9%20d%27un%20objectif
Record 7, Spanish
Record 7, Textual support, Spanish
Record 8 - internal organization data 2003-12-16
Record 8, English
Record 8, Subject field(s)
- Audiovisual Techniques and Equipment
- Photography
Record 8, Main entry term, English
- automatic camera
1, record 8, English, automatic%20camera
correct
Record 8, Abbreviations, English
Record 8, Synonyms, English
Record 8, Textual support, English
Record number: 8, Textual support number: 1 DEF
A camera with a built-in exposure meter that automatically adjusts the lens opening, shutter speed, or both for proper exposure. 1, record 8, English, - automatic%20camera
Record 8, French
Record 8, Domaine(s)
- Audiovisuel (techniques et équipement)
- Photographie
Record 8, Main entry term, French
- appareil photographique automatique
1, record 8, French, appareil%20photographique%20automatique
correct, masculine noun
Record 8, Abbreviations, French
Record 8, Synonyms, French
- appareil-photo automatique 2, record 8, French, appareil%2Dphoto%20automatique
correct, masculine noun
- appareil photo automatique 3, record 8, French, appareil%20photo%20automatique
correct, masculine noun
Record 8, Textual support, French
Record number: 8, Textual support number: 1 DEF
Appareil-photo muni d'un posemètre intégré qui règle automatiquement l'ouverture de l'objectif et la vitesse d'obturation, ou les deux, afin d'assurer une exposition adéquate. 4, record 8, French, - appareil%20photographique%20automatique
Record 8, Spanish
Record 8, Textual support, Spanish
Record 9 - internal organization data 1983-08-22
Record 9, English
Record 9, Subject field(s)
- Photography
Record 9, Main entry term, English
- exposure
1, record 9, English, exposure
correct
Record 9, Abbreviations, English
Record 9, Synonyms, English
Record 9, Textual support, English
Record number: 9, Textual support number: 1 OBS
Camera setting of shutter speed and lens aperture that controls film exposure. 1, record 9, English, - exposure
Record 9, French
Record 9, Domaine(s)
- Photographie
Record 9, Main entry term, French
- réglage
1, record 9, French, r%C3%A9glage
masculine noun
Record 9, Abbreviations, French
Record 9, Synonyms, French
Record 9, Textual support, French
Record number: 9, Textual support number: 1 OBS
Combinaison de vitesse et d'ouverture relative déterminant l'exposition appropriée du film utilisé. 1, record 9, French, - r%C3%A9glage
Record 9, Spanish
Record 9, Textual support, Spanish
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