Coordinate Frame rotation (geog2D domain)
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Coordinate Frame rotation (geog2D domain) Open
Coordinate Operation Method Details [VALID]
Name: Coordinate Frame rotation (geog2D domain)
Code: 9607
Operation is Reversible: Yes
Formula: Note: These formulas have been transcribed from EPSG Guidance Note #7-2. Users are encouraged to use that document rather than the text which follows as reference because limitations in the transcription will be avoided.

Transformation of coordinates from one geographic coordinate reference system into another is often carried out as a concatenation of the following operations:

(geographical to geocentric) + (geocentric to geocentric) + (geocentric to geographic)

The Coordinate Frame rotation (geog2D domain) transformation has 5 steps:

(i) geographic 2D coordinates are converted to 3D using EPSG coordinate operation method code 9659;

(ii) geographic 3D coordinates are converted to geocentric coordinates using EPSG coordinate operation method code 9602;

(iii) the middle step of the concatenated transformation, from geocentric coordinates to geocentric coordinates, uses the Coordinate Frame rotation (geocentric domain) method, EPSG method code 1032;

(iv) the geocentric coordinates are converted to geographic 3D using EPSG coordinate operation method code 9602;

(v) finally the geographic 3D coordinates are converted to geographic 2D using EPSG coordinate operation method code 9659.
Example: The same example as for the Position Vector transformation (coordinate operation method 9606) can be calculated, however the following transformation parameters have to be applied to achieve the same input and output in terms of coordinate values:

Transformation parameters Coordinate Frame rotation convention:
tX (m) = 0.000
tY (m) = 0.000
tZ (m) = 4.5
rX (") = 0.000
rY (") = 0.000
rZ (") = -0.554 = -0.000002685868 radians
dS (ppm) = 0.219

from which M = 1.000000219

Please note that only the rotation has changed sign as compared to the Position Vector transformation.
Method
Parameters:
Parameter Name Parameter Code Sign reversal Parameter Description
X-axis translation 8605 Yes The difference between the X values of a point in the target and source coordinate reference systems.
Y-axis translation 8606 Yes The difference between the Y values of a point in the target and source coordinate reference systems.
Z-axis translation 8607 Yes The difference between the Z values of a point in the target and source coordinate reference systems.
X-axis rotation 8608 Yes The angular difference between the Y and Z axes directions of target and source coordinate reference systems. This is a rotation about the X axis as viewed from the origin looking along that axis. The particular method defines which direction is positive, and what is being rotated (point or axis).
Y-axis rotation 8609 Yes The angular difference between the X and Z axes directions of target and source coordinate reference systems. This is a rotation about theY axis as viewed from the origin looking along that axis. The particular method defines which direction is positive, and what is being rotated (point or axis).
Z-axis rotation 8610 Yes The angular difference between the X and Y axes directions of target and source coordinate reference systems. This is a rotation about the Z axis as viewed from the origin looking along that axis. The particular method defines which direction is positive, and what is being rotated (point or axis).
Scale difference 8611 Yes Scale factor for source CRS axes minus one, where the scale factor is a multiplication factor to be applied to coordinates in the source CRS to obtain the correct scale in the target CRS. dS = (M – 1). If a distance of 100 km in the source CRS translates into a distance of 100.001 km in the target CRS, the scale difference is 1 ppm (the ratio being 1.000001). When the scale difference dS is expressed in parts per million (ppm), M = (1 + dS*10-6). When the scale difference dS is expressed in parts per billion (ppb), M = (1 + dS*10-9).