Eye4Software Hydromagic - Knowledge Base - Geodesy
| Q200001 | Do you have an up-to-date list of all supported local map projections ? |
| A regularly updated list of all supported local map grids and their corresponding parameters can be found at the URL below. When a grid is not listed, you can add this grid by yourself. Please notify our helpdesk, so we can include it in the next release of the software. http://www.eye4software. ... | |
| Tags: Local Map Grids, Local Map Projections, |
| Q200002 | Do you have an up-to-date list of all supported horizontal map datums ? |
| A regularly updated list of all supported horizontal map datums and their corresponding parameters can be found at the URL below. When a map datum is not listed, you can add this map datum by yourself. Please notify our helpdesk, so we can include it in the next release of the software. http: ... | |
| Tags: Map Datums, Horizontal Map Datums, Chart Datum, |
| Q200003 | Do you have an up-to-date list of all supported reference ellipsoids ? |
| A regularly updated list of all supported ellipsoids (and spheres) and their corresponding parameters can be found at the URL below. When a reference ellipsoid is not listed, you can add this ellipsoid by yourself by entering the flattening and semi-major axis values. Also please notify our h ... | |
| Tags: Reference Ellipsoid, Semi-major Axis, Inverse Flattening, Ellipsoid, |
| Q200004 | I am working on a project in South-Africa. Does your software support Transverse Mercator South Oriented ? |
| Yes this projection method is supported. A list of all supported map projections can be found on our website at the URL below: http://www.eye4software.com/hydromagic/documentation/map-projections/ When a map projection method is not supported, please contact our helpdesk so we can try to help ... | |
| Tags: Map Projection, Map Projection Method, Projections, |
| Q200005 | I am unable to add new map grids. After clicking Save, the changes are lost. |
| This may happen in some circumstances, and the error is related to file system security. You can try the following to fix this problem: Make sure the "C:\ProgramData\Hydromagic\" folder is accessible (read and write access !) for the current user Reinstall the software as Administrator ... | |
| Tags: Creating Grid, Creating Datum, |
| Q200006 | Does your software support the State Plane Coordinate System ? |
| Yes it does, all SPCS27 and SPCS83 map grids are present in Hydromagic. More information on the State Plane Coordinate System can be found here. ... | |
| Tags: Geodesy, State Plane Coordinate System, SPCS27, SPCS83, NAD27, NAD83, |
| Q200007 | How can I change the vertical units ? |
| In Hydromagic the units are linked to the coordinate system (local grid) used. To change the units, you either have to find another version of the coordinate system, or modify the coordinate system to use other units. For more information on how to edit pre-defined local map grids, please refere ... | |
| Tags: Vertical Units, Depth Units, Coordinate System, Local Grid, Local Map Grid, |
| Q200008 | I want to use NADCON to convert between NAD83 and NAD27, is this supported ? |
| NADCON is fully supported, the correction files are also shipped with the application. ... | |
| Tags: NADCON, NAD83, NAD27, |
| Q200009 | Does your software support NTv2 correction grids ? |
| National Transformation version 2 grid files are supported. We even ship a couple of NTv2 correction grids with the software. More correction grids can be downloaded from our NTv2 information page. ... | |
| Tags: NTv2, National Transformation Version 2, GSB files, Correction Grid, OSTN02, |
| Q200010 | What is a geodetic or map datum? |
| A geodetic datum can be defined as a set of constants specifying the coordinate system used for geodetic control, i.e., for calculating the coordinates of points on the Earth. ... | |
| Tags: Geodetic Datum, Map Datum, Datum, |
| Q200011 | What is HARN or HPGN ? |
| A High Accuracy Reference Network (HARN) and a High Precision Geodetic Network (HPGN) were two designations used for a statewide geodetic network upgrade. The generic acronym HARN is now used for both HARN and HPGN and was adopted to remove the confusion arising from the use of two acronyms. A HARN ... | |
| Tags: HARN, HPGN, Map Datum Conversion, Map Datum Transformation Grid, Transformation Grid, |
| Q200012 | Which horizontal datum transformations are supported ? |
| Hydromagic is able to convert between geoidetic datums using one of the following translation algorithms: No transformation Molodensky Bursa Wolf NADCON HARN or HPGN NTv2 ... | |
| Tags: Datum Transformation, Molodensky, Bursa Wolf, NADCON, HARN, HPGN, NTv2, |
| Q200013 | I have to perform a hydrographic survey in the UK. Do you support OSTN02 ? |
| Yes, OSTN02 is implemented as a NTv2 correction grid, and is included in the software by default. ... | |
| Tags: OSTN02, NTv2, Ordnance Survey, Transformation Grid, |
| Q200014 | I am using NAD27 as map datum but the position is about 100ft off |
| When using NAD27, coordinate conversion tages place between NAD83 (WGS84) and NAD27.There are two variants, a matrix transformation or tranformation by a datum shift file.By default Hydromagic is using the matrix transformation. If your map or project is using the datum shift file transformation you ... | |
| Tags: NAD27, NAD83, NADCON, Position Error, Datum Shift, |
| Q200015 | How can I change a grid to use NADCON for NAD27 to NAD83 translation ? |
| By default, all State Plane grids that use NAD27, use a regular (Molodensky) NAD27 to NAD 83 transformation. It is not very difficult to change the built in grid to use NADCON conversion: Make sure you run the software as an Administrator, or make sure UAC in windows is turned off Select the "Mana ... | |
| Tags: State Plane Coordinate System, NAD27, NAD83, NADCON, |
| Q200016 | How can I test if my geoid file is working fine without the need to go to the survey location? |
| To test if a geoid model works as expected (which is recommended before starting your survey), please follow the steps below: " Make sure that the geoid file is correctly installed or downloaded. For more information, please refer to the geoid files manual page: https://www.eye4software.com/hyd ... | |
| Tags: geoid model, installing geoid model, testing geoid model, geodesy calculations, |
| Q200017 | Do you have a WGS84 UTM map projection in US Survey Feet? |
| By default the UTM zones are always in meters. This is because Hydromagic uses the EPSG database which does not include definitions for UTM zones in International Feet or U.S. Survey Feet. Most probably they will be added in new versions anyway. This article explains how to convert any map proje ... | |
| Tags: WGS84, UTM, UTM zones, meters, feet, horizontal units, vertical units, units of measure, |
| Q200018 | I want to use GEOID18B for the United States, how do I know which zone I must use? |
| The GEOID18 model for CONUS (the The contiguous United States) is divided into eight (8) zones to reduce file size and reduce lookup times. To determine which geoid zone you have to use, please have a look at the table below: Zone No. Latitude Range (N) Longitude Range (W) 1 40 ... | |
| Tags: GEOID12, GEOID12A, GEOID12B, GEOID18, NAVD88, geoid model, zones, CONUS, |