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Eng ID Term Definition
3681
parallactic error
See ERROR.
3682
parallactic grid
See GRID.
3683
parallax
An apparent displacement of the position of a body with respect to a reference point or system, caused by a shift in the point of observatio... more
An apparent displacement of the position of a body with respect to a reference point or system, caused by a shift in the point of observation.
3684
parallax: absolute stereoscopic
In PHOTOGRAMMETRY, considering a pair of AERIAL PHOTOGRAPHS of equal PRINCIPAL DISTANCE, the algebraic difference of the distances of the tw... more
In PHOTOGRAMMETRY, considering a pair of AERIAL PHOTOGRAPHS of equal PRINCIPAL DISTANCE, the algebraic difference of the distances of the two IMAGES from their respective PHOTOGRAPH NADIRS, measured in a horizontal plane and parallel to the AIR BASE. Also called horizontal parallax, linear parallax,or x-parallax.
3685
parallax: angular
See PARALLACTIC ANGLE.
3686
parallax: annual
The angle subtended at a CELESTIAL BODY by the radius of EARTH's ORBIT. Also called helio­cen­tric parallax, or stellar parallax.
3687
parallax: diurnal
The difference in the apparent direc­tion or position of a CELESTIAL BODY as observed from the centre of the EARTH and a point on its sur­... more
The difference in the apparent direc­tion or position of a CELESTIAL BODY as observed from the centre of the EARTH and a point on its sur­face. This varies with the body's ALTITUDE and di­stance from the EARTH. Also called geocentric paral­lax.
3688
parallax: equatorial horizontal
HORIZONTAL PARALLAX as observed at the EQUATOR, as it attains its maximum value.
3689
parallax: geocentric
See PARALLAX: DIURNAL.
3690
parallax: heliocentric
See PARALLAX: ANNUAL.
3691
parallax: horizontal
In ASTRONOMY, the GEOCENTRIC PARALLAX of a body on the observer's HORIZON. In PHOTOGRAMMETRY, PARAL­LAX: ABSOLUTE STEREOSCOPIC.
3692
parallax: instrumental (or instrument)
That change which may result from the position in which an obser­ver stands with respect to the FIDUCIAL MARKS on an instru­ment (personal... more
That change which may result from the position in which an obser­ver stands with respect to the FIDUCIAL MARKS on an instru­ment (personal parallax); or by the imperfect ADJUSTMENT of the optics of the instru­ment (optical parallax).
3693
parallax: linear
See PARALLAX: ABSOLUTE STEREO­SCOPIC.
3694
parallax: optical
See PARALLAX: INSTRUMENTAL.
3695
parallax: personal
See PARALLAX: INSTRUMENTAL.
3696
parallax: solar
The E­QUATORIAL HORIZONTAL PARALLAX of the SUN.
3697
parallax: vertical
See PARALLAX: Y-.
3698
parallax: X-
See PARALLAX: ABSOLUTE STEREOSCOPIC.
3699
parallax: Y-
In PHOTOGRAM­METRY, the difference between the perpendicular distances of the two IMAGES of a point on a pair of photographs from the verti... more
In PHOTOGRAM­METRY, the difference between the perpendicular distances of the two IMAGES of a point on a pair of photographs from the vertical plane containing the AIR BASE. The existence of y-parallax is an indication of TILT in either or both PHOTOGRAPHS and/or a difference in flight heights, and interferes with stereoscopic examination of the pair. Also called vertical parallax or want of correspondence.
3700
parallax bar
See STEREOME­TER.