Supported Coordinate Systems
Exhaustive coordinate systems support is one of the advantages of PHOTOMOD
software. PHOTOMOD software installation kit includes coordinate systems database
set. This database set includes the so-called international database
(it consists of coordinate systems for many countries) and also specialized databases
for some countries. It is recommended to use specialized databases, if available, because they
contain comprehensive icoordinate system information for each country. The databases distributed with
PHOTOMOD contain more than 1000 coordinate systems. A user can define his own
coordinate system using the built-in editor.
Types of coordinate systems:
Local Cartesian (coordinate systems on the
Local curved (coordinate systems on the
Topocentric horizontal (coordinate systems
with the origin in the selected space point and axis directions);
Geodetic (curvilinear, latitude / longitude
/ height coordinate system) - in geodetic calculator only;
Projected (coordinate system defined by
the map projection).
Local Cartesian coordinate systems
These are arbitrary oriented local Cartesian orthogonal coordinate systems.
PHOTOMOD software allows to set axis orientation (left or right-hand), axis
labelling and unit. You can add your own units for linear, angular and indimensional
variables. Your unit must be defined via the base unit of this variable type.
Local curved coordinate systems
Local curved coordinate systems differ from local Cartesian coordinate systems
in Z-coordinate correction due to curvature of the Earth (R-radius sphere).
The correction value depends on the selected space point X0,Y0 (automatically
defined in base PHOTOMOD modules, manually defined in geodetic calculator).
The coordinates converting from Cartesian to local coordinate systems executes
User can set sphere radius R, axis orientation (left or right-hand), axis labelling
Topocentric horizontal coordinate systems
In contrast to local curved coordinate systems topocentric horizontal coordinate
systems location is uniquely determined in relation to base geodetic coordinate
system. To define system user must set the origin (latitude, longitude and height)
in base geodetic coordinate system. Z axis lies on ellipsoid surface normal
in origin, one of the plane axis is oriented to the North, the other - to the
East (concrete situation depens of the axis orientation (left or right-hand).
User can set axis labelling and unit.
Geodetic coordinate systems
These are curvilinear coordinate systems. Point position is defined by means
of geodetic latitude, longitude and height over ellipsoid.
PHOTOMOD software allows to set datum, ellipsoid parameters (semi-major axis
and semi-minor axis or back compression), converting parameters to global coordinate
system (Molodensky or Bursa-Wolf transform), prime meridian longitude (if it
is not Greenwich), plane coordinates and height units.
Geocentric (Cartesian) coordinate systems
These are coordinate systems with the origin in the mass center of the Earth
ellipsoid. At that X axis is oriented to the intersection point of prime meridian
and equator, Z axis to the North pole, and Y axis supplements coordinate system
to right-hand triple. User can define prime meridian longitude, datum, axis
labelling and unit.
Projected coordinate systems
These are coordinate system defined by the map projection. PHOTOMOD supports
the following projected coordinate systems:
Transverse Mercator projection
Gauss - Kruger projection (at 6° zones)
UTM (Universal Transverse Mercator) projection (at 6° zones)
Oblique Mercator projection
Oblique Mercator projection (Hotine variant)
NZMG (New Zealand Map Grid) projection
Lambert projection with two standard parallels
Lambert projection with one standard parallel
Lambert projection (Belgium variant)
Mercator projection with two standard parallels
Mercator projection with one standard parallel
Oblique stereographic projection
Polar stereographic projection
Quasi-stereographic projection (Roussilhe projection)
Poly conic projection
Gauss - Boaga projection.
User can define parameters for all projections. User can set prime meridian
longitude, datum or ellipsoid, coordinates labelling and units.
Standard PHOTOMOD delivery set includes special utility - GeoCalculator - geodetic
calculator, designed to convert data from one coordinate system to
another interactively or from text file.