A reference framework consisting of a set of points, lines, and/or surfaces, and a set of rules, used to define the positions of points in space in either two or three dimensions.

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1answer
813 views

getting the specified geographic transformation, or at least the GCS, of a data frame

First, the TLDR digest: I'm getting a bogus value from dataFrame.geographicTransformations on some machines; how do I get the correct value as shown in the properties dialog? and/or Given a spatial ...
3
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1answer
562 views

QGIS custom CRS for map of manufacturing shop floor

I'm working on a web app that shows a map of a manufacturing plant's shop floor. I've built it in Inkscape and QGIS, but when I try to load it into Tilemill, I get a CRS error. Specifically, it ...
3
votes
2answers
316 views

How do you change the prime meridian of a map?

I am working with the Natural Earth world map as a SHP file, but when I try to change the prime meridian (PRIMEM) of the coordinate system ...
3
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1answer
2k views

How to get the coordinate system from a PostGIS database?

My question is probably amazinlgy stupid, but I can't find the answer myself. I would like to extract from a database the latitude and longitude of points. For now, I'm getting x(the_geom) and ...
3
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1answer
438 views

Why are the formats of these coordinates different?

I'm really sorry if this is a silly question (and I'm sure it is) but I have tried searching but I am a complete newbie to coordinates and maps and I don't know what I'm looking for so am not finding ...
2
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1answer
84 views

How to properly open an ASTER data?

Yesterday i downloaded an Aster L1B image from USGS's website. If i load it in QGIS, it doesn't get displayed properly(location wise). Even after i've enabled "On the fly" option, it's not reading the ...
2
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1answer
95 views

Dealing with raster: creating it in projected CRS and exporting it in geographic CRS

When creating a raster from a polygon (the CRS of the polygon is a geographic coordinate system), the raster is created in the projected coordinate reference system of the data frame, which is a ...
2
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2answers
107 views

which map projection should be used for global map with geography and human demographics

I am working on a project to try to identify the most threatened populations (on a global scale) of having a limited access to freshwater. I want to compare those most at risk currently and then add ...
2
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1answer
139 views

Why is shapefile not drawing in expected location after (or before) using Define Projection tool? [duplicate]

I have downloaded this zipped shapefile of bus routes from the City of Houston data portal. I then performed these steps in ArcGIS Desktop 9.3.1: Extracted the shapefile from the *.zip Added this ...
2
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1answer
83 views

Can you create a CRS of superseded NSW Datum

I want to use a superseded projection (NSW integrated survey datum - referred to as ISG) because my main client utilises it. The projection is based on AGD66. We regularly receive survey files in this ...
2
votes
3answers
174 views

Geodesic measurements for short distances throughout US?

My ArcGIS experience has been limited to working on large-scale maps with planar projections. I'm moving to a project in which I want to calculate the distance between pro sports facilities throughout ...
2
votes
5answers
413 views

Is latitude / longitude a universal coordinate system?

I hear people complain: my biggest gripe with google spatial apis is that they hide the fact that latitude/longitude is not a universal coord system My question is Is latitude / longitude a ...
2
votes
1answer
124 views

How do I set the projection and coordinate system for a TIFF file?

I have a topographic map of California (obtained from CAL-Atlas) as a TIFF file. I tried importing it into QGis, but it displays the map using a pixel based coordinate system rather than ...
2
votes
1answer
107 views

Problem converting coordinates

I'm trying to convert punctual values from lat/long to EPSG:6372, a projection for Mexico, defined by the Instituto Nacional de Estadística y Geografía (INEGI). I found a converter online but somehow ...
2
votes
1answer
109 views

Why does same image in two ArcGIS ArcMap configurations show different extent numbers?

I would like to get hear from you about the situation I am seeing here. What It got my eye was that when I download an ASTER from Reverb/ Echo from USGS website. At work, I load my ASTER file to my ...
2
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1answer
454 views

How to align (georeference) images using QGIS?

I'm completely new to all this. I'm trying to make a map of Han dynasty-era China for a mod for a game called Crusader Kings 2. I've downloaded QGIS and Natural Earth 2, but I need this image to ...
2
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1answer
159 views

Why does QGIS 1.8.0 crash when I try to set up CRS on Win XP?

I have a problem with my qgis 1.8.0. When I click on any button that set CRS or try to set the coordinates on the fly, qgis crash. I try to uninstall the program and re-install it again using ...
2
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1answer
156 views

Setting coordinate systems in QGIS: “transform error caught”

I'm learning how to use QGIS (v 1.8.0 "Lisboa") on Mac OS 10.6.8. My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
2
votes
1answer
394 views

Is it possible to convert data from WGS84 to Bessel1841?

When we convert data from bessel1841 to WGS84, parameter setting must be used because it is impossible automatic convert on QGIS. Reference: Converting shp file from bessel1841 to WGS84 Is it ...
2
votes
1answer
260 views

Problems with NAD27 projection in QGIS

I have some data that is in NAD27, but I am having a hard time displaying it in QGIS. I think that the problem is with the CRS. I cannot seem to find the correct NAD27 option. The closest one seems ...
2
votes
1answer
803 views

Reprojection from WGS to Slovenian Gauss Kruger in QGIS

I have gpx file (track) in WGS84 (EPSG: 4326) coordinate system from Garmin GPSMAP 62 which is right projected in BaseCamp and MapSource. When I save track as *.GPX and import it to QGIS and use ...
2
votes
1answer
2k views

Why is my .prj file not being read by QGIS?

First off, I am new to GIS. I am using qgis (1.8.0), and have been given a shapefile containing .shp, .prj, .shx, .dbf, however qgis will not load the .prj file stating an invalid data source. ...
2
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0answers
409 views

PostGIS: ST_Transform function conversion problem

I'm inserting map data from a GML file with srid EPSG:27700 into a PostGIS database table with srid EPSG:4326. I'm using the ST_Transform function as in this snippet: ...
2
votes
3answers
832 views

extract lat/long from screen when using British National Grid projection

Using ArcGIS 10, is it possible to click anywhere on the map (projected to British National Grid), but return the coordinates in WGS84 lat long? Alternatively, when will Streetview work with OS ...
2
votes
1answer
304 views

Two rasters created from the same polygon have different extents?

My problem is that i am trying to export some rasters to Rockworks so that i can create a sand layer from them. Rockworks requires the grid files i use to have the exact same XY co-ordinates. So i ...
1
vote
1answer
86 views

Tiled raster image to be placed in an OSM/ Leaflet.js map

I have a mapoverlay in a custom projection which I need to add as a layer to an Openstreet map within a website. Since I was not able to change the projection earlier, I decided to manipulate the ...
1
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2answers
164 views

How do I convert Geo-Coordinates to Pixel-Coordinates on a Map?

I have an image file that is a Robinson Projection Map of the world. I have a list of geo-coordinates. I would like to find the pixel-coordinates on the map that correspond to my the geo-coordinates I ...
1
vote
1answer
77 views

Can I define a transformation between 2D and 3D in Geotools?

I'm using Geotools, and I need to convert coordinates between 2D and 3D coordinate reference systems. I recognize that there's no universally-correct way to do this: 2D -> 3D means "making up" a Z ...
1
vote
1answer
152 views

Help defining custom CRS in QGIS 2.2

I'm trying to use EPSG:4479 in QGIS. 1) If I search for EPSG:4479, it returns a "Imported from GDAL" EPSG:4479, but it does not work. At the console, the following message is displayed: ERROR 6: ...
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2answers
158 views

How to fix shape file projections

I have a project with several shape files. The files overlapping however. I have to go to unusable extents to even see the file on the same screen. I have tried using to project to as suggested here ...
1
vote
1answer
91 views

Question about BNG coordinate systems

I'm historically a user of MapInfo Professional but have recently started using FME and have been talked into now testing out a copy of QGIS. The main problem I've come across is that the coordinate ...
1
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2answers
207 views

Add custom CRS - 2.2.0 Valmiera

i've builded a custom proj.4 library, tested it by command line (proj and cs2cs) and with postgres/postgis. All works fine. Now i'm trying to make the same with Qgis 2.2.0. I've replaced the original ...
1
vote
1answer
626 views

Eastings/Northings OSGB36 Grid origin

Using this site, we can see that the (approximate) centre of Southampton, UK has OSGB coordinates of 441847,112279. However, looking at the UK grid, where each large square is (500 km)2, then these ...
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0answers
106 views

Intersection between a ray from lat, lon, alt, with pan, tilt and earth's surface

I have a problem that consists of finding the intersection point between a ray from a given lat, lon, alt, that is looking to a given pan and tilt angles and the earth's surface. I need the lat, lon ...
1
vote
1answer
74 views

My Coordinate Reference System listing is in the wrong language

I just installed QGIS Desktop 2.0.1 on a desktop (Windows 8-64). All the menus are in English-US (as they should be), but the CRS listings -- when I try to change them for a project are a layer -- ...
1
vote
2answers
152 views

Is it possible to change CRS without the .prj file?

I'm working with QGIS and trying to change the CRS of some maps. Is is possible to do it without the .prj file? Please let me know. Thanks.
1
vote
0answers
592 views

How to set Scale Factor for Lambert Conformal Conic (LCC) projection in ArcGIS Desktop?

The projection for my state according to my country's Mapping Agency is in a specific Lambert Conformal Conic (LCC) projection. They have given values for the following parameters: False Easting ...
1
vote
1answer
85 views

Setting coordinate systems in gvSIG: workflow or transformation issues

I am learning how to use gvSIG 1.10 (Mac OS 10.6.8 Snow Leopard). My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
1
vote
1answer
102 views

Which SRS is computational more effective to store continental scale data? (given some conditions)

For a Precision Agriculture application I need to make calculations in UTM projection. The data will be stored in Postgis and is made of soil samples results (point data) and field boundaries of many ...
0
votes
3answers
76 views

Defining custom projection using baseline survey coordinates

I have CAD data that I need to incorporate into a GIS analysis. The CAD data does not have a defined projection, but the drawings include a table of survey baseline points. I need to know if I can ...
0
votes
1answer
716 views

Coordinate conversion - Lat Long to State Plane, ArcServer-Silverlight

I am trying to project a Lat/Long value I get from a table to a x/y value that I can use to plot a graphic. I have seen one way to do this may be to use something like this: feature.Geometry = ...
0
votes
1answer
323 views

GCS_WGS_1984 and 900913. What is the difference?

I use WMS Service with mymapproxy/mapproxy.yaml : services: demo: kml: tms: wmts: wms: srs: ['EPSG:4326', 'EPSG:900913'] md: title: MapProxy OSM WMS Proxy abstract: This ...
0
votes
0answers
41 views

what is the difference between the Geographic coordinate, transformed coordinate and screen coordinate [duplicate]

What is the difference between the Geographic coordinate, transformed coordinate(projected) ,cartesian coordinate, and screen coordinate? Is there a live example? And what is the association between ...
0
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2answers
756 views

Setting spatial reference for MapInfo tab-file

How can I change spatial reference for tab-file in MapInfo Professional?