A map projection is any method of representing the surface of a sphere or other three-dimensional body on a plane

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221 views

how can I know which projection has this data?

I have data in an unknown projection to me. I open it in QGIS and I see that the shapes are ok, but I need to identify the projection in order to merge this data with other stuff. The points look ...
11
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1answer
920 views

Great-circle lines in Equirectangular projection

Just to check that I'm on the right track: Are all great-circles on the sphere and in equirectangular projection (i.e. latitude, longitude pairs) either: meridians (i.e. going pole to pole) of the ...
0
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1answer
358 views

How to get DXF to show up in the right spot?

I just followed the advice of this forum post in order to export the vector layers of a PDF for usage in ArcMap. The map vector layers in the PDF were spatially referenced. I was able to export the ...
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1answer
256 views

Having trouble finding out what coordinate system a map is using, and how to convert it

I'm using Small Area shapefiles in Ireland from the Central Statistics Office (CSO) website. The link to these is here http://census.cso.ie/censusasp/saps/boundaries/ED_SA%20Disclaimer1.htm (Look for ...
3
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0answers
522 views

VBA Convert decimal degree to Meters button

I have 2 data frames one which has WGS data in it and the other OSGB1936. I am trying to create a button where the user can input decimal degrees (WGS) and it will zoom them to that location in ...
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0answers
142 views

What is a radar projection?

Trying to overlay a radar image(radar projection) on a mercator projected map, but have no idea about what a radar projection is. So here are my quesions: What is a radar projection? What's its ...
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0answers
265 views

What is UTM Zone 0?

I am currently working with some roadway link data and it is being projected in UTM. After importing the shapefile into GRASS I can view the map and it looks correct but when I view the projection ...
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1answer
613 views

What are Bands, Dimensions, and Histograms in QGIS?

First; I can see a band as synonymous with a channel in an image editing program like GIMP, is this correct? If so then bands play the role of color mixing and masking. Are there any other ...
4
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3answers
3k views

Parameters for ED50 -> ETRS89/WGS84 seven-parameter transformation which are good for Denmark?

I am looking for parameters for a seven-parameter transformation (Rx, Ry, Rz, Tx, Ty, Tz, s) from ED50 UTM (zone 32U) to ETRS89 and/or WGS84. The best match I could find is here: ...
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1answer
220 views

Why are the areas covered by 2 Universal Polar Stereographic (UPS) coordinate different?

According to http://en.wikipedia.org/wiki/Universal_Polar_Stereographic_coordinate_system. the area covering Arctic is less than Antarctic. Any reasons for it? It is due to the shape of the lands?
0
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2answers
318 views

Mercator projection image data

I'm trying to create a map which I can place points on within my application I found some mecator jpg images but in order to accurately place points I need to convert the lat/long to pixels so that ...
2
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1answer
158 views

Determining the transformation between a satellite image and long/lat

I'm trying to overlay some data onto a satellite image of the UK. The image is a hi-resolution version of the image below (originally from dundee university): ...
4
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2answers
4k views

Error 000735: Input Dataset or Feature Class: Value is required

I am a true novice when it comes to ArcGIS and computer programs like this one. Am taking a class and cannot get the Project function to work under the tool box. The path I used was ArcTool box --> ...
0
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1answer
228 views

Projection - Some of my data are in odd position [closed]

Some of my data has this position lon: 181 / lat: 91 So when I try to draw them on the Google map: var geographic = new OpenLayers.Projection("EPSG:4326"); var mercator = new ...
3
votes
1answer
148 views

How to test if two GDAL datasets are in the same projection?

I'm attemping to write a funciton to test if a list of datasets are in the same projection. Naively, I thought I could test the text of WKTs, but that does not work in the following case: ...
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2answers
791 views

Why is Format of output data grayed out on Save As dialog for Rectify?

I started georeferencing and I could not save my new "rectify" file, I don't know if is because of the raster or I did something wrong. Then I find out that my control layer is not accurate, it ...
1
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1answer
368 views

PROJ.4 custom projection that is Transverse Mercator with Affine post-process

I am trying to define some of my local TMAF grids in PROJ.4 so I can reproject points between the local grid and MGA95 and/or WGS84. For these grids I have the MapInfo CoordSys clause which defines a ...
3
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2answers
1k views

Display two layers with OpenLayers at once

How can i display two layers with diferent projections at once? For example i have layer with EPSG:70076 and OSM layer.
3
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1answer
1k views

Export to new projection in QGIS 1.8

I would like to use QGIS to convert a CSV file from UTM to lat/long. I imported the CSV file with the "Add Delimited Text Layer" plugin. This works fine, the data looks like it is projected properly ...
2
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1answer
628 views

Area calculation: Albers Equal Area vs Pseudo Mercator

I have a question concerning area calculations in South-East Asia for West-East range that goes from India to Eastern Malaysia and a North-South range from Northern India to Indonesia (xMin,yMin ...
3
votes
1answer
1k 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
2k views

ArcGIS 10.0/10.1 - arcpy - automate projection tool with different datum or projection

I am getting stuck with a task that is slightly different from the posts I found so far on this same website. Assumption: all layers have a defined coordinate system Problem: I would like to ...
27
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2answers
20k views

What's the difference between EPSG:4326 and EPSG:900913?

I am a bit confused on EPSG:4326 and EPSG:900913. I thought that they were both same. Though as I am placing my features over GMaps, which is EPSG:4326, I need to define the srsname of the WFS layer ...
2
votes
1answer
321 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 ...
0
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1answer
337 views

How can I find and fix broken raster metadata using QGIS?

I have a raster (TIFF) hillshade image that I would like to use in a mapping project. However, I'm having a hard time lining it up properly in QGIS. Through a series of investigations, I have ...
6
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1answer
137 views

Is there a name for map projections that produce two disks?

I've seen lots of world maps in the shape of two disks that touch, each one a separate projection of one hemisphere onto a disk -- usually the Western Hemisphere and the Eastern Hemisphere -- so ...
0
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1answer
435 views

How do I add a Corel Draw map as .dxf file to QGIS and how do I georeference it?

I have a vector data map of Poland, which I exported from Corel Draw. I can display the map in QGIS. At first the boundaries and subdivisions are only displayed as lines, after saving the data as ...
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0answers
150 views

Converting altitude in feet to pixels on a mercator map image

I know the question might seem farfetched given that the map is 2d. But I essentially want to project items-aircraft-above the map and I would like their altitude to be vaguely 'realistic' in terms of ...
0
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1answer
811 views

Which area measurement to trust? - The same polygon in GoogleEarth v. ArcGIS [duplicate]

Possible Duplicate: What is the most accurate coordinate system for calculating areas of polygons? I'm currently involved in comparing the "official metropolitan" areas of several cities ...
1
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1answer
125 views

Python error when running SpatiaLite with OSGB(27700)

I have a project open in QGIS and am trying to import an Ordnance Survey Address Point layer into SpatiaLite. I have recently installed the Qspatialite plugin. I open SpatiaLite in the DB Manager ...
4
votes
2answers
432 views

How do I Capture GDAL projection and create matching output (OGR or GDAL) shape files?

Working in C++, using GDAL and OGR: Depending on what the user has supplied for image input, I need to output point (or other) shape files in the same projection as the input raster images. The ...
6
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1answer
666 views

Coordinate system in aerial imagery

I am calculating WGS84 coordinates of points in an aerial image, given the WGS84 coordinates of the center of the image and the ground distance width and height (calculated from altitude and lens ...
2
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2answers
272 views

Why are the output point shapefile PRJ files empty?

I have tried evry thing I could find (using C++) to create a new .prj file for an output point shape file using OGR. While I get no compilation or execution errors and ArcMap accepts the file as a ...
2
votes
2answers
460 views

How to avoid exceeding latitude and longitude limits, when importing a .csv file?

I am currently working with a project with "on the fly"-projection (WGS 84 / UTM zone 32U). Now I want to import a csv. file with points, which have a longitude and latitude using the "Add Delimited ...
2
votes
0answers
369 views

Mapserver+openlayers: displaying a shapefile with Cylindrical Equal Area (Lambert) projection

I have some shapefiles in "World Cylindrical Equal Area (Lambert) projection". The .prj reads: PROJCS["World_Cylindrical_Equal_Area",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_ ...
3
votes
1answer
102 views

Projectionless shapefile with unknown source

I have a bunch of maps that are output from a land use model in .asc format, but none have a projection file associated. The person who originally ran the LU model is long gone, so I don't have access ...
2
votes
2answers
2k views

Howto change OpenLayers BBOX request projection?

My map uses EPSG:900913 projection on the map. All coördinates in the database are stored in the 'normal' google format / GPS coordinates (WGS84). For instance, if you save a new location..Before I ...
0
votes
1answer
242 views

Terrasolid - How to define spherical mercator (EPSG: 3857)

Im trying to define the srs EPSG 3857 inside Terrasolid sofware. I ran into a problem because the definition of the reference ellipsoid is given with a major axis and inverse flatening, not via both ...
9
votes
5answers
4k views

Better Distance Measurements in Web Mercator Projection

I am working with an ESRI stack, storing my layers in a sql-spatial-enabled-SDE- geodatabase (Geometry type, Web Mercator-3857). I am building a web mapping application, so by default, the tiles are ...
4
votes
1answer
712 views

Openlayers and Geoserver fail to reproject while editing Vector with WFS-T

I can't get the Openlayers and Geoserver work with WFS-T editing a vector layer. I have a layer of points where the Native SRS is EPSG:32639. After trying a lot of combinations, I ended up with two ...
7
votes
2answers
768 views

Bertin 1953 map projection settings

I am trying to use the Bertin 1953 map projection, as described in the book "Semiology of graphics" by Jacques Bertin. But I can't find the settings in any of my GIS software. Does anybody have a ...
6
votes
2answers
444 views

What projection does the global climate region map from Wikipedia use?

I would like to use this global climate region map from Wikipedia as a "basemap" (by plotting over the image in R). Is it possible to determine the projection of this map?
1
vote
1answer
3k views

How to Project shapefile from NAD 1983 UTM Zone 12 to WGS 1984 UTM Zone 13N?

I have a question and I have a shapefile that is in NAD UTM Zone 12 and Datum is North American Datum of 1983. What I would liket to reprojection it to NAD 1983 UTM Zone 13N and change the Datum to ...
5
votes
1answer
5k views

How to re-project shapefiles?

I wanted to re-project a QGIS project, but there is no such option. When searching for an answer I see ogr2ogr suggested for this task, by re-projecting each vector layer (shapefile in this example). ...
2
votes
1answer
530 views

OpenLayers Vector Layer not aligned with Google Oblique Imagery

Check http://jsfiddle.net/vasile/BKvcX/6/ In the first map, the yellow line should follow the street curve, however if you pan the map up-down, you clearly see the misalignment due to what ? ...
2
votes
2answers
904 views

What is the SRS code for Lambert Conformal Conic projection and GCS Everest Definition 1962?

I have a shapefile with Geographic Coordinate System is "GCS_Everest Definition 1962" and the Projected Coordinate System is "Lambert_Conformal_Conic". I want to add this shapefile in Geoserver. But I ...
2
votes
0answers
207 views

projection discrepancy with gdal (1.9) and proj4

I boiled the problem down to that python example: import sys try: from osgeo import gdal from osgeo import osr except: import gdal import osr if __name__ == '__main__': version_num = ...
4
votes
1answer
1k views

OpenLayers Map with custom SRS (without EPSG code) [closed]

Is it possible to show geodata by OpenLayers in custom projection? I want to show my geodata in OpenLayers interface. Source layer(s): shape-file(s), standard epsg:4326 lon/lat projection; ...
3
votes
1answer
342 views

Problem in displaying a GeoTiff image in JMapFrame

I'm trying to display a GeoTiff image with no projection but where the geographical extent (bounding box) is known: reader= format.getReader(new File(sImageName)); GridCoverage2D gridCoverage= ...
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vote
1answer
146 views

Idaho's southern border looks curved in ArcMap. How do I make Idaho look flat?

I have a polygon of Idaho's borders in ArcMap. The southern border of the state is slightly curved. I realize that the Earth is curved in reality, but I want Idaho to look flat. Is there a way to do ...