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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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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351 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 ...
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612 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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200 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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322 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
767 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 ...
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22k views

Coordinate system and projection for georeferencing Google Maps image in ArcGIS Desktop?

I have saved Google Maps image (not Google Earth) of area at latlon(17.692437,83.218689) by some method in jpeg format. It is an exact snapshot of the Google Maps. Now I need to geo-reference it to ...
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1answer
234 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?
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Leaflet and EPSG 4326 Projections

UPDATE: LEAFLET fixed support for EPSG 4326 (LL84) in the latest betas: https://github.com/Leaflet/Leaflet/issues/1207 Leaflet says it supports EPSG 4326 (Plate Carree, aka ll84) projections. I think ...
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1answer
254 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): http://www.bbc.co.uk/news/uk-scotland-...
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7k 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 --> ...
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281 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 OpenLayers.Projection("...
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15k views

Which is correct projection in ArcGIS Server for EPSG:3857/900913?

I want to publish a mapservice in ArcGIS server, which will be overlayed on Google Maps or Bing Maps. For this, the Map Service needs to be in EPSG:3857/900913. The Google Maps projection is supposed ...
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1answer
231 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: 'PROJCS["...
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1k views

ArcPy 10.1 PointGeometry.projectAs()

I'm trying to reproject an X,Y passed in from an Add-in. So far this works fine: pointGeometry = arcpy.PointGeometry(arcpy.Point(x,y),srIn,False, False) projectedPoint = pointGeometry.projectAs(...
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226 views

Mercator projection that shrinks toward pole

I've noticed that lots of map viewer (especially those nautical chart viewer) will shrink a mercator projected chart while panning towards poles. Is this some compensation for mercator distortion? ...
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1k 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 doesn'...
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2k 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 ...
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1answer
474 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 ...
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1answer
829 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 74....
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1answer
3k 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 ...
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754 views

Calculating projected distance using ArcObjects?

I am pretty new to this and I am not sure I understand all the concepts, so I might be using words wrongly or obviously not getting some details right. We mean to do those calculations within our ...
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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 ...
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3answers
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EPSG 3857 or 4326 for GoogleMaps, OpenStreetMap and Leaflet

The discussion at What is the difference between WGS84 and EPSG4326? shows that 4326 is just the EPSG identifier of WGS84.. Wikipedia entries for Google Maps and OpenStreetMap shows that they both ...
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1answer
370 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 ...
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1answer
441 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 ...
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1answer
157 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 ...
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1answer
610 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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179 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 ...
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1k 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 ...
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363 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 ...
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1k views

How to re-project the EASE (Equal Area Scalable Earth) grid with a ~25 km cylindrical projection to WGS84 0.25 degree?

I have nc files. from the metadata ,the projection is cylindrical and the resolution is 25 km: indrical NC_GLOBAL#ease_resolution=25 NC_GLOBAL#history=...
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1answer
148 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 ...
3
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1answer
480 views

USGS GeoTiff extent via GDAL

I have 2006 land cover GeoTiff from the USGS site (for a county in VA, USA). The projection is Albers Conical Equal Area Units. The download came with an HTML metadata file that tells me the geo ...
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1answer
868 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 ...
3
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2answers
444 views

Question Regarding Interpretation of Openlayers BBOX in 4326 Projection

I have a BBOX strategy in my Vector layer, which is sending HTTP GET Requests to my server in order to get the features I wish to display. The projection of the layer is EPSG:4326, so it is my ...
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2answers
564 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 ...
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419 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_ 1984",...
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1answer
10k views

What is the default projection in Leaflet?

I've read an API documentation for Leaflet on its site, but I can't realize: what is a default projection to view maps? It was written about spherical and elliptical Mercator and Equirectangular - so ...
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288 views

How to overlay 3 different layers using ArcMap

I have to overlay 3 different layers called "Bacino Isonzo Perimetro", "Bacini Tributari Isonzo", and "Isonzo" in ArcMap. Layers'properties are shown below. BACINO ISONZO PERIMETRO Data Type: File ...
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1answer
284 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 ...
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2answers
577 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 ...
8
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2answers
3k views

use proj4 to specify Robinson projection with R ggmap and ggplot2 packages?

I want to project this map in robinson projection: library(ggmap) world <- map_data("world") ggplot() + geom_path(data = world, aes(long, lat, group = group)) ...
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513 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?
6
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1answer
8k 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). ...
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2answers
2k views

How can I improve my Georeferencing results?

Background This is my second question related to georeferencing naked raster maps in order to re-visualize them on different coordinate systems and in conjunction with other data layers. The previous ...
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2answers
765 views

High Resolution Sinusoidal Interrupted Projection of the Earth

My grandfather built a rather large globe 10 years ago and never got to complete it (he started drawing about a fifth of it by hand and just gave up after that). I have been looking for a sinusoidal ...
2
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1answer
211 views

Difference between NAD83 Indiana SPW in QGIS and ArcGIS for Desktop?

It seems ESRI and QGIS don't have the same definition for my most commonly used projection, NAD83 StatePlane Indiana West (US ft). When I create data in an ESRI product the projection shows up in ...
2
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2answers
317 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
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0answers
229 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 = int(gdal....