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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775 views

TileStache + OpenLayers TMS - Tiles are rendered disorderly

I newly turned to TileStache to render Mapnik tiles because of the caching option. Before, I was using Mapnik python bindings only and it was working perfectly. Now that I use TileStache, the tiles ...
2
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1answer
232 views

Miller cylindrical projection - central meridian

I'm new to projections topics and I've got a question that may be silly, but I hadn't found answer so far. I'm trying to use Miller's cylindrical projection for converting osm lat/lon to x,y values. ...
2
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1answer
301 views

Viewshed analysis and coordinate systems ArcGIS 10.1

I am trying to run a viewshed analysis and I've downloaded DEM data from the UK ordnance survey (Landform-panorama). Since the data is in ASCII format I have created a seamless raster mosaic (and used ...
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1answer
37 views

Equidistant projection for northern Delaware

I'm just getting started on a long-term project involving northern Delaware. Most of my distances will use great circle distances from the lat/lon, but for a few applications I'll wind up using ...
2
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1answer
712 views

Qgis OSM and layer projection problem

I am using QGIS 2.1.0, and trying to import my vector layer(parcels) with OpenStreetMap layer. My vector layer (parcels) use EPSG 31277 coordinate system. This is the definition for EPSG 31277: (+...
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1answer
171 views

Why are Bounding Coordinates not as expected? [closed]

I have a shapefile in GCS_WGS_1984 projection, but the bounding coordinates/Feature extent shows the wrong coordinates in the screenshot below. . I tried to change the projection, by deleting the *....
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1answer
240 views

How to get projected centroids in QGIS?

I am trying to get a centroid for several polygons on a global scale, in a way that it would correctly represent the common centre of all the polygons, taking Earth's curvature into account. The ...
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1answer
526 views

Why do points shift when reprojected from WGS84 to a state plane coordinate? [closed]

We have a Trimble unit we use to collect equipment. We collect the data in WGS84 and differentially correct it and then reproject it to a state plan coordinate system. The points always shift the ...
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2answers
1k views

Where did the polygons go after projecting a map in QGIS?

I'm fairly new at GIS know-how, but I've run into a problem with a projection of a world map. I have a shapefile of all countries I downloaded from Natural Earth. After projecting it into a ...
3
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1answer
225 views

What are the set of projections that can be accurately georeferenced using polynomial 2?

Background I'm starting with a map from the internet (Encyclopedia Britannica) and georeferencing it using QGIS 2.0.1, I get really accurate georeference solution using polynomial 2 transformation: ...
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1answer
778 views

Choosing correct proj4string in R for a set of points

I was given a set of points which I eventually will overlay with a polygon shapefile in R. The issue is that the person who provided me with the points did not give them to in long/lat coordinates but ...
2
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2answers
584 views

Data points Imported into QGIS are in the middle of ocean

I'm new to QGIS and tried importing some GTFS data in the CSV format (stops.txt). The project CRS, base map CRS and GTFS CRS have all been set to Google Mercator, but the points that are supposed to ...
2
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1answer
95 views

Change the projection at runtime (OpenLayers)

How do I change the projection on an existing Map object? I'd like to allow a user to switch between cylindrical (EPSG:4326) and custom-declared projections with the click of a button.
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2answers
407 views

Calculate distance in QGIS, wrong geographic projection?

I'm trying to do the following: I have 2 shapefiles, one containing all the public schools in NY, another one containing the hotspots in NY (both in points form). Now what I'm trying to do is ...
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2answers
1k views

How to transform a PostGIS bounding box?

I need to query the bounding box of a table (in WGS 84, srid 4326), and transform it to Web Mercator to be consumed by an OpenLayers map. Currently, I am using this to retrieve the bounding box: ...
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1answer
412 views

How to rotate sphere when using Vertical Near Side Perspective projection?

Situation Data is currently displayed on a globe using the Vertical Near Side Perspective projection with a blue circle as a backdrop. Problem I would like to 'rotate' the globe by altering the ...
2
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2answers
227 views

Set projection/CRS in map and shapefile to produce buffer

I simply want to create a buffer of a specific size, around a single point. When I create a buffer it uses degrees/ or radians, or whatever, and the buffer is created that covers the whole screen. I ...
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121 views

Doubt in Field Calculator

I am working in an project.I have a point Shapefile its projection is NAD83(HARN)Pennslyvaniasouth(ftUS)*EPSG3365* when I measure its distance(between two points) it gives me the answer in feet .yes ...
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2answers
304 views

How do I Fix Projection Issues in QGIS

I have some exiting shape files that supposedly have a CRS of OSGEO:41001. If I import new data, and set the CRS to OSGEO:41001 they do not align. If I change the CRS of the new layers to EPSG:4326,...
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1answer
577 views

Coordinate systems and bearings

Ok so I've got a noodle scratcher and want some input before I open my mouth to my higher-ups. I recieved a new boundary description from a surveyor that uses metes and bounds in the form of bearings ...
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7answers
5k views

What strategies, criteria, or rules to use for selecting coordinate systems?

What strategies, criteria, or rules do you use for selecting coordinate systems for (a) storing, (b) analyzing, and (c) displaying GIS data? (I humbly offer my reply to a related question ...
2
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1answer
307 views

Heads up digitizing - Polygons overlay differently with two different Satellite images

I have been digitizing building footprints from satellite image using ArcGIS 10.1 . Field data collections is done with the use of four corner point GPS way point. Due to multipath errors, we are ...
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1answer
657 views

Change coordinate system of a WMS service

I have a WMS service that is projected to UTM/SAD-69. My workspace is in WGS-84 with no projection. I want to change the coordinate system of my WMS service. Is it possible in ArcMap 10.0? The wms ...
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2answers
375 views

No prj file output from qgis:reproject

I'm trying to reproject a vector layer using the 'qgis:reproject' algorithm in the processing/sextante module of QGIS, from Python. This kind of works, but the .prj and .qpj files created after ...
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1answer
239 views

Different output from running algorithm in toolbox and from script

I am unable to get the same results when running the qgis:reproject tool from QGIS processing toolbox (QGIS version 2.0.1) as when running it from a Python script (console). In this example I am ...
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0answers
24 views

Implementing day night functionality [duplicate]

I want to implement day/night functionality on world map i.e there will be dark layer showing countires having night now. This world map could be creaeted through ESRI or SVG map.I want to ...
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1answer
450 views

Waterman Projection in ArcMap

Anyone have any idea how to create (or where to find) the Waterman "Butterfly" projection in ArcMap?
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1answer
410 views

Reprojecting Natural Earth dataset to World Eckert I

My question is connected with QGIS 2. Could anybody explain me how I ought to reproject the Natural Earth dataset there in order my world map to look correctly? When I strive to reproject these data I ...
3
votes
1answer
445 views

QGIS display does not reflect projection

I have slight experience with ArcGIS, but am new to QGIS. I'm trying to set the projection of my map, and I understand that this is done by altering the CRS (coordinate reference system) of each ...
2
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3answers
1k views

What is the projection of an Android Location class instance?

What is the projection of a Location object returned from the LocationClient by a class implementing the LocationListener interface with a fused provider in the Google Play Services SDK? For example, ...
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0answers
854 views

Fortifying re-projected shapefile for ggplot2 in R

I have a shapefile of US county boundaries which I got from the NHGIS. I can load the file using the rgdal package and see information about it: library(rgdal) shp_1860 <- readOGR("shp", "...
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1answer
677 views

OpenLayers using GoogleMaps layers: issues with setCenter and transform

Past week or so I have been doing everything in just OpenLayers and has been going great: been using markers, vectors, bringing in json data via php, and some ajax. Everything has been in one layer ...
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1answer
168 views

GeoTIFF without projection?

I have encountered a GeoTIFF raster files with EPSG:4326 (WGS84), i.e. no projection defined! Is this normal? I would expect raster to be in Projected Coordinate System. Raster is a grid of pixels so ...
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388 views

openlayersplugin qgis 2.0.1

I have installed qgis 2.0.1, great thing... but.. open layerplugin doesn´t work proper. When I try to load two different open layers I get the answer "could not draw google satellite because:" Also ...
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2answers
173 views

How to translate WIGeoEU projection from ArcGIS to Qgis?

I have a Layer with this projection in ArcGIS: PROJCS["WIGeoEU",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0....
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0answers
48 views

Layers with the same Geographic Coordinate system don't overlap [duplicate]

I am a GIS newbie. I'm having a problem that, from the looks of things on this website, is a fairly common problem. I have 3 layers, all in the same GCS that do not line up. I have read all the the ...
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vote
1answer
958 views

Adding Basemap and changing projection - still not aligned

I am using the basemap in ArcMap10 to create a shapefile of hand digitised polygons based on building outlines. However, when I change the basemap projection to Brit Nat Grid, it does not line up ...
2
votes
2answers
148 views

Is it possible to have another CRS in the status bar than used for the map?

I am new to QGIS. When I use OSM or Google Maps as a basemap via Open Layer Plugin, the map should be projected as EPSG: 900913. However, the Coordinates shown in the status bar are useless for me, ...
2
votes
4answers
4k views

Export to new projection in QGIS 1.7

Suppose I have layers A and B. I don't know their projections but by the looks of the map I know they are not the same. In QGIS 1.6 I would use one of my favorite features: Vector> Data ...
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1answer
90 views

cannot get EPSG of bounding box

I use openlayers 2.12. I created a form where the user can insert a bounding box, to insert to the database a new borough. To check the EPSG of the borough I tried the following //ba bb bc bd came ...
3
votes
1answer
175 views

Problem with projection in layer

I'm having problems with visualizing a layer which is in EPSG:4326 Apparently the geometry looks perfect, but I don't know why, it's not in real coordinates. I have projected it to 4326 with QGIS, ...
0
votes
2answers
1k views

Appropriate map projection for the UK?

As the title: what is the most appropriate projection to reduce distortion, if I'm just showing the UK on a map? Is WGS84 fine (since it's a relatively small area), or should I use some other kind ...
2
votes
1answer
181 views

How to reproject EPSG:102218 with QGIS?

I have a raster file. ArcMap says it is in NAD_1983_USFS_R6_Albers (EPSG:102218). QGIS says it is in USER:100000 - * Generated CRS (+proj=aea +lat_1=43 +lat_2=48 +lat_0=34 +lon_0=-120 +x_0=600000 +...
6
votes
2answers
93 views

Define projection at the record level

Hopefully this isn't too dumb a question, but is it possible to define projection at the record level, instead of a whole layer or table? I want to create a "project" database for all the work my ...
2
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0answers
20 views

Draw cirlcle on Equirectangular projection [duplicate]

I'm trying to draw a circle (actually a great circle) on an equirectangular map to archive something like this http://i.stack.imgur.com/7EliU.png (from here). So I have the lat/lon coordinates of the ...
2
votes
1answer
2k views

GeoTools and PostGIS with ESPG:3857

I'm trying to use both PostGIS and GeoTools with the same ESPG:3857 projection, however, it looks like the projections in PostGIS and GeoTools differ. This is what I have in PostGIS: PROJCS["WGS 84 ...
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votes
1answer
172 views

Good projection for covering most of the world

I'm writing an application for building navigation routes thru the city streets, and not quite sure what projection would be best. I tried EPSG:3587, however, the tools I'm using - GeoTools and ...
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1answer
81 views

What should this projection be in OpenLayers?

This is esri rest prj, "spatialReference": {"wkt": "GEOGCS[\"GCS_WGS_1984\",DATUM[\"WGS84\",SPHEROID[\"WGS84\",6378137.0,298.257223563]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0....
3
votes
2answers
607 views

Partial Map Pixel Projections

I have the following: A PNG or JPG of a random width and height, in pixels, that represents a partial map of the world (i.e. a rectangle of the United States). The four corners of this image are ...
3
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2answers
651 views

Geostationary Satellite Projection

What is the equation needed for forward and inverse transformation of Geostationary Satellite projection.?. How to convert it to Geodetic and vice versa. Geostationary satellite projection is ...