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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72 views

Partial loss of projection data converting to MapInfo File with OGR

I'm trying to convert some data from ESRI Shapefile to MapInfo TAB format using ogr2ogr. The data is projected using the British National Grid (EPSG:27700). The output file is valid, and the geometry ...
0
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0answers
62 views

GeoTiff using GDAL

How can I project a tiff using the position of the four corners where the picture have to be placed ? The tiff file has no georeference or projection information I have got a grid with values of ...
2
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1answer
105 views

How to transform this PostGIS type of projection to EPSG:900913 in OpenLayers?

I have transferred this kind of projection from this type(which I don't what type it is): 010100000054E077E6F8F33640FD87F4DBD7AD4340 to EPSG:900913. I have the points which are in the above format ...
2
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1answer
52 views

Python Geospatial Development Error

I'm working through some examples in the Python Geospatial Development book by Erik Westra. On page 439, about setting up a tile map server, he gives the following code for calculating a bounding ...
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2answers
128 views

Mercator vs. Web Mercator for Large Scale Topographic Maps

I have 8 terabytes of imagery that is in either lon/lat or UTM projection that I will be using for the basis of large scale topographic maps. I have been studying the differences between Mercator and ...
0
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1answer
53 views

Convert height Geoid EGM96 to ellipsoidal?

I'd like to convert the height data which is in EGM96 to Orthometric projection. Perhaps there are tools, like ArgGIS (I cannot find if ArcGIS can do this), or any formula that may help me.
2
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0answers
44 views

QGIS CRS correct, but layers appear warped

I am trying to overlay a raster Landsat 8 scene and vector scene boundary. Both are using WGS 84 + UTM48N. However, the vector (orange line) appears offset when overlaid on the raster. I have checked ...
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0answers
48 views

reprojecting (unprojecting) in MrSID decode (SDK)

I am using the C++ SDK (version MrSID_DSDK-9.1.0.4045-win32-vc9). I'm trying to read in arbitrary .sid files and extract rectangular sections of them that can be displayed on top of a "web mercator" ...
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1answer
10 views

Why my map just grayscale mode after use MRT?

i just follow the step to change .hdf file to geotiff file from this site http://duncanjg.wordpress.com/2012/12/11/loading-modis-ndvi-time-series-into-postgis-raster/#comment-1214 and i use data from ...
0
votes
2answers
163 views

How to store lat/long in PostGIS database? [duplicate]

I have a bunch of points in a text file that are represented using lat long (116.3158516 39.9748016). I import them into my GIS enabled database and create trajectories using st_makeline() as ...
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0answers
35 views

Can I get Geoserver to return a WMS in gnomonic projection?

I need to be able to pass in the center lat and long. I have tried using the AUTO Namespace for SRS (which works) but this only supports a few projections, the closest being orthographic. I have ...
2
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1answer
132 views

Definitive list of Proj4 supported coordinate systems

I need to determine the minimum set of coordinate systems supported by all tiers of my project's stack. I have a list of EPSG codes supported by Oracle and GeoServer but I'm having trouble finding a ...
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0answers
50 views

Appropriate reference system for small-scale mapping of the Middle East

I want to create a thematic map of the Middle East that displays certain historic places and regions on a small-scale map (between 1:6.000.0000 and 1:12.000.000). The map has to center the boundary ...
0
votes
1answer
241 views

OpenLayers 3 drag and drop interaction with custom projection problem

I am trying to add layers by using drag and drop interaction. Here is jsfiddle.http://jsfiddle.net/anuket/umdwzn10/ It almost works, I mean new layer is added, but for Geometry it gives "NaN". Geojson ...
2
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3answers
129 views

matching coordinate systems by transforming and projecting

matching coordinate systems of all my data (transforming, projecting) My data uses the GCS_Bessel_1841 coordinate system. Would there be any inaccuracies if i would transform it to DHDN 3-Degree ...
1
vote
1answer
38 views

Mapnik tiles have latitude distortion, projection issue?

I'm trying to work out a kink in setting up mapnik-node. My geos are in postgis, and I allllmost have them rendering properly, but my GIS experience is lacking so I can't seem to determine why this ...
2
votes
0answers
70 views

Mine Grid to UTM

I have been given spatial data (lidar) that was collected in mine grid feet in ASCII format. I am using arc to process but need to define a projection does anyone know how to do this or any other ...
2
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2answers
47 views

Formula for charting a course around the globe, given a location and degree heading?

I'm looking for a formula that takes a long/lat coordinate and a degree heading, (e.g. "I'm standing in San Francisco and I'm facing 45º from north"), and which can draw a line across a map projecting ...
2
votes
2answers
72 views

Overlaying misaligned DGN file in ArcGIS for Desktop?

I received a DGN file, I believe created in Bentley 8, and there is a bit of a misalignment problem. The dgn, when overlain on a Bing Maps aerial or NAIP image, shows up about 20 m or so off. I'm set ...
3
votes
0answers
167 views

Formula for maximum coverage of a geostationary satellite based on earth station elevation

I am trying to create a javascript function to represent the maximum coverage of a geo satellite for different antenna elevations (0 degrees, 5 and 10 degrees) with 3 leaflet polylines. The result is ...
4
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3answers
130 views

Geometric Operations in GIS Systems

I have worked with 2D geometry for CAD - My questions are general and relate to understanding operations on geometric entities (lines). Should geometric operations such as line-line intersection be ...
2
votes
1answer
63 views

Proj4js: Is this correct implementation of Azimuthal Equidistant relative to an arbitrary center?

If I wanted to interpolate points along a Great Circle Arc, it makes sense that either endpoint of the Great Circle is a satisfactory starting place. Next, I suppose I'll need a projection to preserve ...
1
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1answer
39 views

Transforming Robinson to Equirectangular

I need convert this http://bioval.jrc.ec.europa.eu/products/gam/images/large/access-map.png (is it robinson?) to Equirectangular (ESPG:32662) How can i get this using gdalwarp?
4
votes
2answers
111 views

Is there a command line tool for converting projection in .prj and GeoTiff to EPSG codes?

Is there a command line tool to convert a shapefile projection in the .prj file into corresponding EPSG code? I know that there is website http://prj2epsg.org/search for doing this online, but I ...
0
votes
1answer
139 views

Regional Large Scale Map Projection Choice

I am currently designing a geospatial product that will be primarily used for large and intermediate scales that cover an entire state of the US or more. The UTM projection would be ideal because of ...
2
votes
1answer
177 views

Calculating Grid Convergence for Lambert Conformal Conic

What is the formula to calculate Grid Convergence angle (angle between true north and grid north) for Lambert Conformal Conic projection for a given location. Searching online, I have been able to ...
2
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2answers
97 views

Choosing country projections

Anyone know of a good reference (either pay or open-web) that details recommended country projections?
3
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0answers
39 views

Distortion in projected raster

I am having a frustrating problem with something that I think should be very simple. I have a number of DEMs from the National Elevation Dataset (NED), that come standard in the NAD83 coordinate ...
2
votes
1answer
248 views

Georeferencing a raster using GDAL and Python

I want to georeference a raster using python and GDAL. My current approach is to call gdal_translate and gdalwarp using os.system and an ugly list of ground control points. I'd really like a way to do ...
2
votes
0answers
37 views

Project lines onto surface in QGIS

This question may already be answered so please point me in the right direction. I am designing a water distribution system for a rural village in Guatemala. I have created contours for the area. I ...
0
votes
1answer
91 views

How to create an interrupted Mollweide map in R?

I am wondering if it is possible to create an interrupted Mollweide map in R. This question is similar to Discontinuous or Interrupted map projections? which does not really have a satisfactory ...
1
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2answers
50 views

Correction spatial reference

Please assist me on how to use ArcCatalog to confirm the spatial reference is correct and adjust if necessary.
1
vote
1answer
77 views

Set default projection of geometry objects in arcpy

I have a script that creates a polyline geometry from scratch using some math to generate coordinate pairs. At the same time, there is a user-defined polygon shapefile that is used to "erase" the ...
9
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0answers
323 views

Geotransformation for polar stereographic?

I'm currently working to import CANGRID climate data (provided as Surfer Grid ascii, ".grd" files) into ArcGIS. The grid is 95 rows by 125 columns in size.Metadata provides lat/lon of origin (lower ...
1
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0answers
70 views

Clustering the WGS84 point features (projection transformation aspects)

My question is quite trivial and was discussed many times before (like here) but in our case it has the confounding extra requirements... The list of sparsely distributed 2d point features is stored ...
3
votes
1answer
92 views

How to plot a full hemispheric orthographic projection in R

I want to make a plot like that using R: All I want is the country borders as seen from outer space, no fancy colors needed. It seems I need to use the spTransform function, but it gives me a "non ...
1
vote
1answer
177 views

Difference between ETRS89 / ETRS-TM32 and ETRS89 / UTM zone 32N

In QGIS I can choose among other things between "ETRS89 / ETRS-TM32" and "ETRS89 / UTM zone 32N". In my test project both projections displayed the layers at the very same place. So, where is the ...
3
votes
1answer
108 views

Trouble calculating areas in QGIS using field calculator

I am testing various projections to calculate areas using ICES statistical shapefiles and the QGIS field calculator. I am using ICES areas downloadable from the following link: ...
2
votes
1answer
77 views

QGIS crashing when using 'save as' to save a new projection

Every time I try to save a layer with a new projection using 'save as' my QGIS crashes. The new files are there but they seem false. Please see two screenshots attached, one before and one after I ...
6
votes
2answers
284 views

Is there a standard for the specification of .prj files?

We use shape files for data exchange. I've looked at the .prj files: different programs produce different prj files. Is there a standard how the parameters must be specified in a prj file? AFAIK the ...
1
vote
1answer
121 views

Problem with projection of Slovenian Shapefile in QGIS

I hope someone can help me for this: I'm doing my masters thesis in Slovenia (in the field of wildlife management), for this I got a Shapefile of slovenian data by the University. As a main layer, I ...
2
votes
1answer
117 views

Proper projected coordinate system for Minnesota for measuring areas

I have seen in ArcGIS many different State Plane systems for Minnesota (location coordinates in WGS84: 44,07 lat/-94,61 long) within the Projected Coordinate system group: NAD 1983 (CORS 96) ...
0
votes
0answers
37 views

Pros and Cons of a latitude adjustment grid vs other methods of area calculations

When working with high resolution global raster data in WGS 1984 I often need to calculate areas. Now the traditional way for me to achieve this has been to reproject the data to an equal area ...
0
votes
0answers
46 views

How can one use Google Maps API to mimic QGIS projection/CRS

I used QGIS to find the extents of a list of features. However, the resulting data auto-generates the CRS and changes it from WSG84 to a custom one. Is there a way to use the autogenerated CRS in ...
1
vote
1answer
75 views

Difference between source SRS and target SRS in Raster Warp function

Hello I am trying to change a raster layer projections from WGS84 to a custom Lambert layer using 'Raster' --> 'Projections' --> 'Warp' function. I have been asked for source SRS and get SRS. what is ...
1
vote
1answer
88 views

How can I reproject a layer in a spatialite database

I'm writing an android mobile application and, for performance reasons, I want to reproject my layers to match the basemap's projection. Is there a command to do that?
2
votes
2answers
77 views

Custom projection problem with proj.4

I have some vector files that come without projection. So I have to define my own projection in QGIS. The information that comes with the data reads as following: Projection: Lambert Azimuthal Units: ...
0
votes
0answers
54 views

Precision loss when transforming coordinates systems in GDAL (vector layers)

Anybody knows the order of magnitude of the error introduced when transforming coordinates using GDAL? More specifically, I would like to know if significant error is introduced when the ...
1
vote
1answer
35 views

ArcMap Area Calculations vs MultiNet FEATAREA Field Discrepancy

I'm finding a huge discrepancy between the values supplied in the FEATAREA field in my MultiNet data and the area calculation results from ArcMap v10.2.2. In this case, I'm looking at the area of ...
2
votes
1answer
484 views

openlayers display projection

I'm displaying coordinates in epsg:900913 using ol.control.MousePosition() with OSM. I'd like to convert these on the fly in another epsg:2154. I call in the header : <script ...