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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7
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2answers
497 views

How to determine projection parameters when customizing a projection

I am trying to customize an Albers and a Hotine Oblique Mercator (HOM) projection to minimuze distortion in the region I am analyzing. The region extends from about 51 to 62 degrees latitude, covering ...
2
votes
1answer
191 views

domain for transverse mercator projection, using proj.4

I have to apologize for the naive question -- it's my first encounter with projections and this software package, and I intend to use it for a non-geographical application (hence I work on a unit ...
13
votes
2answers
2k views

Calculate distortion outside a UTM zone

One of my colleagues is working with data that is spread across two UTM zone. The majority of the data is in one zone, with a few outliers in another zone. He would like to know what the area ...
9
votes
1answer
435 views

An example Tissot ellipse for an Equirectangular Projection?

I am trying to calculate distortion of an equirectangular projection via Tissot indicatrices. I have tried following the directions on this post (among other things) but it is beyond my understanding ...
8
votes
2answers
371 views

how to produce a Peirce quincuncial map?

As far as I know neither PROJ4 nor ESRI tools can apply the Peirce quincuncial projection. Does anybody know what libraries/softwares can manage it?
3
votes
1answer
204 views

Is there no EPSG code to use for Behrmann equal-area projection in ogr2ogr?

I'm trying to use ogr2ogr to reproject some shapefiles. The projection I wish to use is Behrmann equal-area. I cannot find an EPSG code to use for the '-t_srs' part of the syntax. Is there any way ...
3
votes
1answer
516 views

Calculate bounding box + buffer for rendering a map tile with mapnik library

Mapnik library has a Projection object (I'm using Python bindings): spherical_mercator = '+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null ...
1
vote
2answers
368 views

GeoTools Oblique Mercator Example

I would like to use the Oblique Mercator projection in GeoTools. I'm currently using a WGS84 Mercator projection like this: final CoordinateReferenceSystem wgs84CoordSystem = CRS ...
2
votes
3answers
2k views

Problem with spatial reference system / shapefile projection

I am new to using QGIS and having some problems getting some shapefiles to project correctly. I am using publicly available shapefiles for New York City municipal boundaries found here: ...
1
vote
1answer
437 views

Projecting Imported NetCDF file correctly?

I have 360 NetCDF files (.nc) that I need to import into ArcGIS. They hold monthly historical climate data in the U.S. When I tried to import one, using the Make NETCDF Raster Layer tool, the ...
2
votes
1answer
720 views

Convert shapefile in NAD27 from meters to decimal degrees to match xy data?

I have a shapefile of a boundary (polygon) that has the following projection: NAD_1927_UTM_Zone_11N Projection: Transverse_Mercator False_Easting: 500000.00000000 False_Northing: ...
2
votes
1answer
230 views

Mercator Didn't work on Geoserver

Got some problem with Mercator in Geoserver, I tried to display Flight Information Region that has been stored in my Postgre. The result is more likely drawing using Cartesian projection: I tried ...
1
vote
0answers
1k views

How to project geographic coordinates (lat/long) to a cartesian system (albers equal-area)?

I am using this matlab package http://www2.ocgy.ubc.ca/~rich/map.html#examples to project the latitudes,longitudes of my data to a specific projection. For this particular case I am using albers ...
2
votes
1answer
736 views

Defining datum for Lambert Azimuthal Equal Area and converting to geographic coordinates

I posted this question to a specialised mailing list for spatial data analysis using R here but didn't recieve a response. I am working with shapefiles and rasters in R, and I am unsure if I am ...
3
votes
1answer
202 views

1944 Cyprus Grid coordinate data projection problem in MapInfo

I have coordinate data from the 1944 British Army General Staff, Geographical Section (GSGS) Cyprus map which was cast on the Cassini projection, but was referenced to the Clarke 1880 ellipsoid where ...
5
votes
1answer
511 views

Custom Geographic Transformation on QGIS

Is there a way to create a custom geographic transformation with specifics parameters in QGIS like in ArcGIS? Okay, I want to tranform SAD69 system into WGS84. Well, I'm in doubt because in ArcGIS ...
2
votes
1answer
91 views

Need software to read geo information from tif

I am trying to verify the lat/lon and ECEF values that I have determined for a very specific and unusual situation (a geotif file), and it would be great if I could find some software to read them. ...
4
votes
2answers
5k views

Arcmap 10 feature with undefined coordinate system projects incorrectly when projecton is defined

I'm fairly new to GIS, and am slowly feeling my way through ArcMap 10. I have run across a problem defining the Geographic Coordinate System and projection for a feature (the feature currently has an ...
6
votes
1answer
369 views

Create Mercator map with arbitrary center/orientation?

I want to see a Mercator map where I choose what latitude/longitude is in the center and what direction is "north". In some sense, a Mercator map of a rigid rotation of the globe. Does such a ...
1
vote
3answers
595 views

PRJ file for Stereo70 S-42 projection

I receive lots of Romanian maps with the projection STEREO70 with Datum "S-42 for ROMANIA". I have only found the "Stereo 1970.prj" by ESRI, and when I open the maps with my GIS software the ...
1
vote
0answers
111 views

How to compute a map-to-screen transformation?

Every projection calculation I have come across dealing with the Lambert Conic projection converts the given Lat & Long to meters. So now the magical question: how on earth do you take the meters ...
4
votes
3answers
1k views

Convert an arbitrary meta-data-free map image into QGIS project

My background: experienced programmer, amateur historian, complete beginner to GIS (so I'm using QGIS). I did learn to use the QGIS georeferencer tool though. The input: suppose I have an image like ...
4
votes
2answers
392 views

Why isn't valid geometry not valid in NetTopologySuite when close to poles?

I have a Polygon which crosses the south pole: Polygon in WKT: POLYGON((5.86826073458095 75.6638564054071,-16.5436836399021 63.2220742891438,-19.3664667294083 59.846221066959,-21.7009816876343 ...
1
vote
1answer
231 views

QGIS Projections

I am new to the GIS world and have faired pretty well with ArcGIS 9.3, learned and still learning on the job. I would like to get a better handle on QGIS though. I linked the files from my dropbox. I ...
4
votes
1answer
148 views

What is the most appropriate Projection for the Gulf coast region?

What are the most appropriate datum and projection I could use for the Gulf coast region - spanning Louisiana, Mississippi, Alabama, and Florida? I have to analyze block group data along the coast. ...
23
votes
4answers
2k views

How does one calculate distortion on Equirectangular Projection?

I am trying to calculate distortion so I can distort overlaying text and forms to precisely match an image of an equirectangular projection. So, how does one calculate the distortion at a given ...
1
vote
0answers
250 views

A WMS layer fails to show at some scales

I am tring to overlay my WMS layer on Google but at a particular scale it doesn't show the data of my layer. What can be the problem? <html xmlns="http://www.w3.org/1999/xhtml"> <head ...
6
votes
2answers
262 views

Projections appropriate for global analysis that preserve area and that preserve distance (but not necessarily in the same projection)

I am looking for a projection (or a set of projections) that decently preserve distances so that I can buffer every country in the world and have a similar level of minimal distortion for each. I ...
4
votes
1answer
837 views

How to use DotSpatial to project/reproject shapefiles on the fly

I would like to use DotSpatial to reproject shapefiles on the fly before loading them to GeoServer. I've been looking for tutorials on how to get started with this in vain. Any pointers on where I can ...
2
votes
1answer
375 views

Uploading unprojected shape files using GeoServer REST API

I have a number of shapefiles that lack the .prj file. I'm able to upload them to geoserver using the rest api. However, I'm unable to serve them after upload. Which brings me to the question as to ...
1
vote
1answer
173 views

Looking for CRS for NAD 83 UTM Zone 30N

I'm curious as to why the UTM zones are incomplete for NAD 83 in QGIS? I have a WGS84 shapefile that I would like to project to NAD83 UTM Zone 30N but can't find it in the QGIS CRS list. I see how ...
2
votes
3answers
243 views

coordinate definitions from nyc.gov open data SpatialLocation field

The NYC Open Data website has a dataset of street events. The last column is called SpatialLocation, and is defined as a text field. An example is below. It is clearly two points on a physical map. ...
3
votes
2answers
358 views

Is NAD 83 the same as EPSG:4326?

I'm getting mixed messages about these projections. For example -Is this projection below, NAD 83, 4326? GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983", ...
3
votes
1answer
207 views

2 Shapefile vectors will not plot properly in same space

There are slight differences in 2 shapefiles projection information. I have activated on-the-fly, but they do not plot in the same space. I tried to save as new shapefiles with the same CRS, but ...
1
vote
1answer
434 views

Reprojecting non 4326 WMS image to spherical mercator

In OpenLayers, I'm trying to display a WMS overlay (EPSG:4269) from a server I don't have control over to a spherical mercator projection. Is there an equivalent to this: ...
2
votes
0answers
35 views

Why did my shapefile distance get smaller after changing the projection? [duplicate]

Possible Duplicate: Layers having the same coordinate system should overlap, but they don't. What's wrong? I'm working with a shapefile that has a geographic coordinate system and I ...
5
votes
2answers
374 views

Mass-update the projection in compressed GeoTIFF files

I have a huge set of compressed GeoTIFF files. Someone forgot to set the projection while creating the GeoTIFF files and I would like to add it now. If I use gdalwarp -t_srs source.tif ...
0
votes
1answer
1k views

Conversion from N,E to Lat/Long And Lat/Long to N,E will always be same? [closed]

I have an excel tool for the conversion of following lat/long: Lat: 23° 11’ 24.67503’’ S Long: 118° 46’ 6.15742’’ E , which gives me following N,E: Northing: 7,434,317.43 Easting: 680,991.69 But I ...
1
vote
0answers
173 views

On the usage of Proj4Js->tmerc.js

I am using "proj4js & open layers" for my mapping. I got projection & datum (which is based on "Transverse Mercator") of a local plane and this plane is part of a grid which returns ...
4
votes
1answer
585 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 ...
2
votes
1answer
178 views

How to add FP_WGS_84_IBCAO_Polar_Stereographic projection to QGIS?

I have a GeoTiff image that is projected (see below) I would like to add this projection to the list of CRS in QGIS. Can someone help me do this? Thank you very much in advance!!! Francis ...
0
votes
2answers
171 views

How do you pass parameters for Proj4js implementation with OpenLayers

I am using Proj4js along with OpenLayers for the transformation of x,y (projection type is Transverse Mercator) to long, lat. While executing "inverse()" method what I noticed that in tmerc.js some ...
2
votes
1answer
448 views

How to transpose the lat/lon coordinates of a shapefile?

I need X to be Y and Y to be X (switching lat/long) within the polygon shapefile. If it were a point shapefile I know I could simply reverse the lat/long or x/y parameter and import from a table. I'm ...
1
vote
1answer
127 views

Tool For Generating Formula for Projection

I am using Proj4Js for northing,easting to lat,long transformation. My Datum is "AGD84" and projection is "Transverse Mercator". While doing so I found that if I don't specify "+proj" parameter in ...
1
vote
1answer
967 views

Generating Map Tiles for MGRS Grid Graticule

I'm possibly a bit out of my league here, but ready to get my hands dirty. I want to generate map tiles for a MGRS grid graticule similar to http://tiles.mapbox.com/mapbox/map/afghanistan-mgrs. I ...
4
votes
1answer
1k views

Distances in {Plate Carrée projection - EPSG:4326 - WGS84}

So, "4326 is just the EPSG identifier of WGS84" [3], indeed http://spatialreference.org/ref/epsg/4326/html/ says it is a GEOGraphic Coordinate System: GEOGCS["WGS 84", DATUM["WGS_1984", ...
2
votes
1answer
789 views

Projection ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33 to UTM33N - WGS84

Hi I'm having trouble to reproject a shape file in Qgis. The projection is supposed to be "ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33" and I would like to project it to UTM33N - WGS84 (EPSG 32633). ...
2
votes
3answers
266 views

Are there WMS servers providing maps of UTM zones, actually in the zone projection?

There are lots of EPSG:4326 (lat lon) services out there but if one has to use an UTM projected map as base layer to display utm scenes, are there any WMS endpoints publicly available for that?
2
votes
3answers
364 views

C++ coordinate class that automates projection?

Can anyone point me to a C++ class for representing coordinates that automatically handles projection transforms? What I'm thinking of is something that would allow me to create vars that incorporate ...
1
vote
2answers
332 views

How to shift the Map a little bit?

I'm having trouble with two maps, both UTM33N/WGS84. They should be exactly on top of each other but there is a slight shift between them of probably a few hundred meters or so. I Tried to adjust ...