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Eng ID Term Definition
3701
parallax correction
A CORRECTION due to PARALLAX, particularly that SEXTANT ALTITUDE correction due to the difference between the apparent direction from a poin... more
A CORRECTION due to PARALLAX, particularly that SEXTANT ALTITUDE correction due to the difference between the apparent direction from a point on the surface of the EARTH to a CELESTIAL BODY and the apparent direction from the centre of the EARTH to the same body.
3702
parallax difference
In PHOTOGRAMMETRY, the dif­ference in the ABSOLUTE STEREOSCOPIC PARALLAXES of two points imaged on a pair of PHOTOGRAPHS. Customarily used ... more
In PHOTOGRAMMETRY, the dif­ference in the ABSOLUTE STEREOSCOPIC PARALLAXES of two points imaged on a pair of PHOTOGRAPHS. Customarily used in determination of the difference in ELEVATIONS of ob­jects.
3703
parallax in altitude
GEOCENTRIC PARALLAX of a body at any ALTITUDE. The expression is used to distinguish the PARALLAX at the given ALTITUDE from the HORIZONTAL ... more
GEOCENTRIC PARALLAX of a body at any ALTITUDE. The expression is used to distinguish the PARALLAX at the given ALTITUDE from the HORIZONTAL PARALLAX when the body is in the HORIZON.
3704
parallax inequality
The variation in the RANGE OF TIDE or in the SPEED of TIDAL CURRENTS due to the continual change in the distance of the MOON from the EARTH.
3705
parallel
A circle (or approximation of a circle) on the surface of the EARTH, parallel to the EQUATOR and connecting points of equal LATITUDE. Also c... more
A circle (or approximation of a circle) on the surface of the EARTH, parallel to the EQUATOR and connecting points of equal LATITUDE. Also called paral­lel of latitude.
3706
parallel: astronomical
A line on the surface of the EARTH which has the same ASTRONOMICAL LATITUDE at every point. Because the DEFLECTION OF THE VERTICAL is not th... more
A line on the surface of the EARTH which has the same ASTRONOMICAL LATITUDE at every point. Because the DEFLECTION OF THE VERTICAL is not the same at all points on the EARTH, an astronomi­cal parallel is an irregular line, not lying in a single plane.
3707
parallel: celestial
See PARALLEL OF DECLINATION.
3708
parallel: geodetic
A line on the SPHEROID which has the same GEODETIC LATITUDE at every point. A geodetic parallel, other than the EQUATOR, is not a GEODETIC L... more
A line on the SPHEROID which has the same GEODETIC LATITUDE at every point. A geodetic parallel, other than the EQUATOR, is not a GEODETIC LINE. In form, it is a SMALL CIRCLE whose plane is parallel with the plane of the GEODETIC EQUATOR.
3709
parallel: geographic(al)
A line on the EARTH having the same LATITUDE at every point. The term is appli­cable alike to an ASTRONOMICAL PARALLEL or to a GEODE­TIC P... more
A line on the EARTH having the same LATITUDE at every point. The term is appli­cable alike to an ASTRONOMICAL PARALLEL or to a GEODE­TIC PARALLEL.
3710
parallel: ground
In PHOTO­GRAMMETRY, the intersection of the plane of the PHOTO­GRAPH with the plane of refe­rence of the GROUND. See also AXIS OF HOMOLOG... more
In PHOTO­GRAMMETRY, the intersection of the plane of the PHOTO­GRAPH with the plane of refe­rence of the GROUND. See also AXIS OF HOMOLOGY.
3711
parallel: isometric
In PHOTOGRAMMETRY, the inter­secting line between the plane of a PHOTOGRAPH and a horizon­tal plane having an equal perpendicular di­stan... more
In PHOTOGRAMMETRY, the inter­secting line between the plane of a PHOTOGRAPH and a horizon­tal plane having an equal perpendicular di­stance from the same PERSPECTIVE CENTRE.
3712
parallel: photograph
In PHOTOGRAMMETRY, the IMAGE on a PHOTOGRAPH of any horizontal line in the object space which is perpendicular to the PRINCIPAL PLANE. All p... more
In PHOTOGRAMMETRY, the IMAGE on a PHOTOGRAPH of any horizontal line in the object space which is perpendicular to the PRINCIPAL PLANE. All photograph parallels are perpendicular to the PRINCIPAL LINE. The photograph parallel passing through the PRINCIPAL POINT is the principal parallel and that passing through the ISOCENTRE is the ISOME­TRIC PARAL­LEL.
3713
parallel: principal
See PARALLEL: PHOTOGRAPH.
3714
parallel: standard
A PARALLEL of latitude which is used as a control in the computation of a map PROJECTION. For a tangent cone, this is the PARALLEL of tangen... more
A PARALLEL of latitude which is used as a control in the computation of a map PROJECTION. For a tangent cone, this is the PARALLEL of tangency. For a secant cone, the two PARALLELS of inter­section are the standards.
3715
parallel motion protractor
See PROTRACTOR.
3716
parallel of altitude
See ALMUCANTAR.
3717
parallel of declination
A circle of the CELESTIAL SPHERE parallel to the CELESTIAL EQUATOR. Also called celestial parallel.
3718
parallel of latitude
See PARALLEL.
3719
parallel plate
An optical disk with optically flat, parallel surfaces; used especially in optical MICROME­TERS.
3720
parallel rulers (or rule)
An instrument for transfer­r­ing a line parallel to itself.