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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ArcGIS 10.2.1 projection Issue - Everything shifted west 50 m

I just completed hand-digitizing features on some NAIP (NAD83) imagery as a shapefile (NAD83...or that's what I thought I was doing). The coordinate system for the dataframe was NAD83, but now when I ...
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2answers
2k views

How to “calculate” distance-to-ground of all 18 OSM zoom levels?

Assuming I'm building a 3D solution with the "world" being mapped to global geo-data supplied by OSM / Cloudmade... think http://www.webglearth.com but with completely different goals and use-cases. ...
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1answer
110 views

Obtaining length of non projected feature (gcs_wgs_84) in meters instead of decimal degrees?

I could not find a post which answered to my problem and I hope I didn't miss it, in case I did I apologize. I'm working with Arcgis 10 and I have a multiple lines feature with gcs_wgs_1984 ...
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83 views

Change SHP Projection to display on Google Map

I'm pretty new to GIS but not to programming, so sorry if this was already asked. I didn't find a solution not sure if I didn't quite understand everything about Projections and so on. I have a GIS ...
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46 views

ESRI/Mapinfo MGA56 prj vs QGIS MGA56 prj

I am trying to understand why the degree unit is different between ESRI/Mapinfo and QGIS: ESRI/Mapinfo ...
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3answers
411 views

Which projection is best for mapping the contiguous United States?

If I wanted to project latitude & longitude data for the contiguous United States (the United States excluding Alaska and Hawaii), which projection would I use? I prefer more accurate distances ...
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30 views

How can I create a warp mesh to match two close but not identical datasets together?

I have two datasets for Mars. One of them is the Mars Viking color mosaic, the other the Mars Global Surveyor black and white imagery. When I overlay the two datasets, it becomes obvious that the ...
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2answers
4k views

What are the units of the calculated area from a raster in decimal degree

I'm trying to calculate area for a raster file which contains 2 layers (0 for unsuitable habitat and 1 for suitable). It's been calculated successfully but I don't know what is the unit of the ...
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19 views

Error in projection Qgis [duplicate]

qGIS- when I try to project using +proj=robin +lon_0=-150 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs In order to centre on the Pacific I get this: Any advice? Thank you!
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36 views

Raster displaying in ArcGIS

Can anyone please explain this to me? I need the image to be displayed right in any case as I will be using it in different programs. When I open this raster image in an existing ArcGIS map it ...
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64 views

Raster overlay with different projection in Google Maps

I have a map created with Google Maps. I want to overlay over some data I am downloading dynamically, covering the whole world. That data is a matrix as follows: 1024 values for the longitude ...
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14 views

Misaligned layers unknown projection [duplicate]

I have two datasets for Rio de Janeiro, Brazil that come from the same original dataset and are almost exactly the same. However, one has been projected into an unknown projection. Both were at some ...
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2answers
47 views

Overlaying Shapefile with projection and raster (without projection but with defined extent) using QGIS?

I'm trying to overlay a shape file into a raster. The raster has no defined projection but it's a global raster with extent 0, -1800 : 3600, 0. I tried "on the fly CRS" transformation and followed the ...
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2answers
61 views

MMQGIS:Create:Hub Distance: Output shapefile in wrong coordinate system

I have a QGIS-project that is completely in EPSG:31467 - DHDN / Gauss-Kruger zone 3. It consists of random points (camera traps) surrounded by a polygon (forest edge). I already converted the polygon ...
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82 views

UTM ED 50 transformation to WGS84

I have a set of navigation shot points (pre 1975) with coordinates that are based on a UTM ED50 zone 33 projection and I need to transform these to WGS84. My procedure has been to load the excel fine ...
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3answers
208 views

Plotting Netcdf data. How to get right projection?

Maybe it's very easy for someone to fix, but I'a a new one in R, so I really need help. I/m trying to plot data containing lat, lon and variable (nmf2). The grid isn't a regular one, so there are some ...
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1answer
30 views

Guessing unknown projection of Webapp

I have a series of points around the greater london area (may be also around 100-200kms away from it) like those here in the format Lon, Lat: 43032.1,32681 95816.5,34473.8 15439.3,-13987 The ...
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1answer
79 views

Ogr2ogr trying to import and convert shapefile to EPSG:3857

I'm attempting to import a shapefile (along with .prj file) to MySQL using Ogr2ogr and using the t_srs option set to EPSG:3857 (the default for Leaflet and Google Maps) but I'm getting odd results, ...
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1answer
619 views

Projection to use with satellite image from Google Maps / Earth

I'm very new to anything concerning GIS so please forgive me if this question has been asked before, but I assure you, I've been trying to find an answer for quite some time now. Of course it is ...
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1answer
216 views

How to Buffer data in a Geographic coordinate system?

I am having an issue with buffer. My data is in Geographic coordinate system. I am trying to do a buffer of 600m and i am finding different results for each case, have tried thse so far: Map in web ...
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31 views

How to set projection parameters in ArcGIS?

I would like to open .hdf satellite data(FY-3 from China) in ArcGIS, but there is unknown projection info in it. The extent of hdf is : top: 0 right:1383 bottom:-586 left:0 And the projection ...
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28 views

Polygon Shifting in WGS 84

I'm troubleshooting some discrepancies between intersection results in State Plane and WGS 84. The intersect was ran when both the polygons and points were same PCS ...
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1answer
80 views

How to add a lat/lon grid to a map using azimuthal projection?

I have a north azimuthal projection, equal areas. I want to create a map from it (in QGIS) and display a grid on it for better orientation. Thats how it looks like: Why doe my degrees have so ...
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47 views

Which projection should be chosen to model transmission lines across the USA?

I am looking at different options for high voltage power lines in the US. These power lines cross several states. Since in the end the distance is of importance, is the USA Contiguous Equidistant ...
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1answer
49 views

How do I interpret this proj4string and why doesn't changing units change its resuls?

I'm new to GIS - I have a background in statistics. I have the following proj4string: '+proj=lcc +lat_1=40.66666666666666 +lat_2=41.03333333333333 +lat_0=40.16666666666666 +lon_0=-74 +x_0=300000 ...
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1answer
41 views

Determine projection of a shapefile

Is there anyway to determine projection of a shape file which doesn't have .prj file? I am trying to re-project this shape file to another projection, I know that it is Lat long data. I could manage ...
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1answer
110 views

World map different projection

I want to display something on a world map. I have these shapefiles http://thematicmapping.org/downloads/world_borders.php I want my map to look something like this: or I am using QGis. Is ...
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1answer
120 views

QGIS: How to add a second polygon that is exactly 5km larger in all directions?

Given is a map with an airport. Within a distance of 5km around the runway there is a so called no fly zone for drones (in Switzerland). I want to show this zone in a map. What I would like to do is ...
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722 views

Appropriate map projection for the Pacific Ocean

I've found this map that shows the Pacific Ocean from http://www.transpacificproject.com: I'd like to produce a similar map, for the same region of the earth and I'd like to use the same projection ...
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44 views

Overlay polygons on raster in different projections

I'm overlaying polygons on a raster to get the average value inside the polygon (using SAGA->Shapes-Grid->Add grid values to shapes in the QGIS Processing Toolbox), using a geographic and a ...
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40 views

Project Raster Data Loss - 2 Billion People

I am using the SEDAC/CIESIN raster data for population counts. This data is in WGS1984, and I want to project this data to a Fuller projection. After running through "Project Raster" in ArcMap 10.1, ...
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25 views

Projection issue in gwp-openlayers

We are trying to display wms laying that uses EPSP 4326 using gwt-openlayers. Here is a sample of its url: ...
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1answer
91 views

Different projections in the same shapefile

I was just wondering if it was possible to change the projection of only certain objects in a shapefile, while the others remain the same. I have to insert points onto a map, and some of them are in a ...
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2answers
199 views

How to load projection along with raster in R?

Why the operation myraster = raster("test.asc") does not load the associated projection file test.prj located in the same directory as test.asc? Does raster() need a specific argument? It seems ...
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2answers
117 views

US map shape distorted in QGIS

I am very new to QGIS and mapping. I am trying to load a US state map shapefile in QGIS. But the problem is it does not look like another US state map available on the internet. The upper part looks ...
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61 views

Surface Volume 3D Analyst tools

I'm using Surface Volume tool (ArcGIS 10.3) to calculate volume of air from a valley. I delimited my DEM (clip tool) and choose Below as plane reference with 603 m as height. The DEM is projected in ...
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1answer
212 views

Difference between 2 projections?

I have osm.xml file where projection is defined as follows: Map background-color="grey" srs="&srs900913;" minimum-version="2.0.0"> n settings.xml file projection is also set there as: <!ENTITY ...
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21 views

ArcGIS Layers same coordinates not lining up [duplicate]

I have a large polygon for a borough, and smaller polygons for the local authorities within it (they divide up the borough). When I add the smaller polygon layers, the polygon appears distorted and ...
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21 views

Changing Area Output - PUMAS

I currently have shapefile of US PUMAS and another feature shape file (call it feature X). I am using arcpy to project both of these files to the following projection coordinate system (using ...
2
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0answers
47 views

Stretching of geometry when rasterizing vector data on Google Maps

I'll start with a quick backstory on what I am trying to achieve. I'm working on an offline Android GIS tool and people are throwing giant datasets at it. It converts these into Google features (V2) ...
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1answer
78 views

How to create buffer around point having projection 4326

I am trying to create buffer (in meters) around point(long lat alt) which is in projection 4326 with below code. But it is not giving expected output. SELECT ...
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1answer
45 views

Generate tiles with stereographic projection

I am developing a web application that shows some information to the user on a map. The application is not connected to the internet, so for the first protoype I generated some map tiles using ...
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2answers
92 views

GDAL - Warping raster to new domain/resolution/projection causes data loss

I am attempting to warp a GTiff from a lat/lon projection to a higher (~2x) resolution Polar Stereographic grid. In the output GTiff any cells north of 64 deg lat become NaN instead of their actual ...
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1answer
54 views

Georeferencing uneven/irregularly gridded rasters

I'm trying to take a set of NetCDFs and turn them into georeferenced datasets using GDAL. However, the only Geospatial data is a set of 2-D lat/lon arrays. The projection type is not lat/lon. THe ...
2
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1answer
34 views

Geowebcache alias for custom projections

Is there a way to configure a projection alias in geowebcache? E.g. if I would like to advertise projection EPSG:25833 and EPSG:32633 to the client, while requesting tiles from the backend using ...
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64 views

ArcMap ModelBuilder: problem with %name% variable when used in iteration for projection

I have prepared a model which should project all shape files ( currently in MUTM 81) in a folder to MUTM 84. But when I use “%Name%” in output dataset for geodatabase as “D:\Soil ...
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2answers
6k views

How to create custom coordinate system in ArcGIS Desktop?

I have a series of control points with xy coordinates in both NAD83 UTM and in a local grid. How can I go about creating a new projection file in ArcGIS 10 for the local grid?
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35 views

Projecting NAD83 on-the-fly to WGS84 [duplicate]

I have a point feature class in a geodatabase that uses WGS84 as its SRS. A colleage of mine created points in this feature class using an external database containing lat and long values. However, ...
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10answers
3k views

Discontinuous or Interrupted map projections?

Do any of the current open source GIS softwares support discontinous projection systems? E.g. sinusoidal, dymaxion, butterfly, etc? If not, are there any affordable commercial ones that do (affordable ...
2
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2answers
138 views

Assigned projection and an unprojected WGS84 geographic coordinate system

I am to be submitting a shapefile for review but the first two requirements have me confused. Are these requirements conflicting or am i just not understanding the question? Requirements: The ...