TERMIUM Plus®
The Government of Canada’s terminology and linguistic data bank.
FOCAL RATIO [5 records]
Record 1 - internal organization data 2002-09-06
Record 1, English
Record 1, Subject field(s)
- Optics
- Photography
Record 1, Main entry term, English
- perspective
1, record 1, English, perspective
correct
Record 1, Abbreviations, English
Record 1, Synonyms, English
Record 1, Textual support, English
Record number: 1, Textual support number: 1 DEF
The apparent relation between the shape, visual scale and position of visible objects ... 2, record 1, English, - perspective
Record number: 1, Textual support number: 1 OBS
The size of identical objects at different distances from the observer appear to be in inverse ratio to their distances. In viewing a photograph, the eye receives the same perspective impression as it would when viewing the original scene if a contact print of the photograph is viewed at a distance equal to the focal length of the camera lens used. 2, record 1, English, - perspective
Record 1, French
Record 1, Domaine(s)
- Optique
- Photographie
Record 1, Main entry term, French
- perspective
1, record 1, French, perspective
correct, feminine noun
Record 1, Abbreviations, French
Record 1, Synonyms, French
Record 1, Textual support, French
Record number: 1, Textual support number: 1 DEF
Qualité perceptuelle de la troisième dimension dans l'espace ou sur une représentation graphique plane, comme un dessin. 1, record 1, French, - perspective
Record 1, Spanish
Record 1, Textual support, Spanish
Record 2 - internal organization data 2002-03-01
Record 2, English
Record 2, Subject field(s)
- Remote Sensing
Record 2, Main entry term, English
- perpendicular vegetation index
1, record 2, English, perpendicular%20vegetation%20index
correct, officially approved
Record 2, Abbreviations, English
- PVI 2, record 2, English, PVI
correct, officially approved
Record 2, Synonyms, English
Record 2, Textual support, English
Record number: 2, Textual support number: 1 CONT
Vegetation monitoring has been one of the main focal points of remote sensing study since remote sensing research began. Many vegetation indices, using red and infrared reflectance, have been devised. The Perpendicular Vegetation Index(PVI), Ratio Index and Normalized Vegetation Index are among the well known indices of this type. The Perpendicular Vegetation Index, proposed by Richardson and Wiegand(1977), was defined as the distance from the soil line on a scatter plot of near infrared(NIR) versus red reflectance. The pixel vectors of bare land in such plots vary with soil moisture content. The PVI was developed as a vegetation index to effectively monitor the vegetation biomass without being affected by differences in soil background. 3, record 2, English, - perpendicular%20vegetation%20index
Record number: 2, Textual support number: 1 OBS
perpendicular vegetation index; PVI: term and abbreviation officially approved by the RADARSAT-2 Terminology Approval Group (RTAG). 4, record 2, English, - perpendicular%20vegetation%20index
Record 2, French
Record 2, Domaine(s)
- Télédétection
Record 2, Main entry term, French
- indice de végétation perpendiculaire
1, record 2, French, indice%20de%20v%C3%A9g%C3%A9tation%20perpendiculaire
correct, masculine noun, officially approved
Record 2, Abbreviations, French
- PVI 2, record 2, French, PVI
correct, masculine noun, officially approved
Record 2, Synonyms, French
Record 2, Textual support, French
Record number: 2, Textual support number: 1 DEF
Indice de végétation utilisé pour la surveillance de la biomasse sans que n'entrent en compte les différences de l'arrière-plan sol. 2, record 2, French, - indice%20de%20v%C3%A9g%C3%A9tation%20perpendiculaire
Record number: 2, Textual support number: 1 OBS
indice de végétation perpendiculaire; PVI : terme et abréviation uniformisés par le Groupe de travail de la terminologie de RADARSAT-2 (GTTR). 2, record 2, French, - indice%20de%20v%C3%A9g%C3%A9tation%20perpendiculaire
Record 2, Spanish
Record 2, Textual support, Spanish
Record 3 - internal organization data 1999-03-24
Record 3, English
Record 3, Subject field(s)
- Photography
- Optics
- Optical Instruments
Record 3, Main entry term, English
- relative aperture
1, record 3, English, relative%20aperture
correct
Record 3, Abbreviations, English
Record 3, Synonyms, English
Record 3, Textual support, English
Record number: 3, Textual support number: 1 DEF
The ratio of the focal length of a lens to the diameter of the effective aperture-the so called f number. 2, record 3, English, - relative%20aperture
Record 3, French
Record 3, Domaine(s)
- Photographie
- Optique
- Instruments d'optique
Record 3, Main entry term, French
- ouverture relative
1, record 3, French, ouverture%20relative
correct, feminine noun
Record 3, Abbreviations, French
Record 3, Synonyms, French
Record 3, Textual support, French
Record number: 3, Textual support number: 1 DEF
Diamètre utile d'un objectif ou d'une lentille par lequel passe la lumière. 2, record 3, French, - ouverture%20relative
Record number: 3, Textual support number: 1 OBS
On le calcule en déterminant le rapport entre le diamètre du diaphragme et la longueur focale de l'objectif. 2, record 3, French, - ouverture%20relative
Record 3, Spanish
Record 3, Textual support, Spanish
Record 4 - internal organization data 1976-06-19
Record 4, English
Record 4, Subject field(s)
- Optics
Record 4, Main entry term, English
- intermediary focal ratio 1, record 4, English, intermediary%20focal%20ratio
Record 4, Abbreviations, English
Record 4, Synonyms, English
Record 4, French
Record 4, Domaine(s)
- Optique
Record 4, Main entry term, French
- ouverture numérique intermédiaire
1, record 4, French, ouverture%20num%C3%A9rique%20interm%C3%A9diaire
feminine noun
Record 4, Abbreviations, French
Record 4, Synonyms, French
Record 4, Textual support, French
Record 4, Spanish
Record 4, Textual support, Spanish
Record 5 - internal organization data 1976-06-19
Record 5, English
Record 5, Subject field(s)
- Optics
Record 5, Main entry term, English
- focal ratio 1, record 5, English, focal%20ratio
Record 5, Abbreviations, English
Record 5, Synonyms, English
Record 5, French
Record 5, Domaine(s)
- Optique
Record 5, Main entry term, French
- ouverture numérique utile
1, record 5, French, ouverture%20num%C3%A9rique%20utile
feminine noun
Record 5, Abbreviations, French
Record 5, Synonyms, French
Record 5, Textual support, French
Record 5, Spanish
Record 5, Textual support, Spanish
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