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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21 views

Creating an Interrupted Map With OGR, Mapnik and PIL

I am trying to create a simple interrupted Sinusoidal map with Python using OGR, Mapnik and PIL. The general idea is: Make 6x 60 degree sinusoidal maps For each one, make a mask to make it gore ...
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1answer
27 views

Dymaxion/Butterfly alternative projection for QGIS

I've been reading the Dymaxion and Butterfly projections are not open source, so can not be used with QGIS. Are there alternatives to these available in QGIS? I'm looking for a single projection so ...
2
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3answers
51 views

South-up projection/setting in QGIS

Is there a south-up setting for a projection in QGIS?
3
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2answers
83 views

Explaining scale decrease inside parallels and outside increase for Lambert conformal conic projection?

For a Lambert conformal conic projection, when projecting the cone on the globe, two parallels are formed and the scale decreases between the two parallels and increases outside them. Why does this ...
2
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0answers
19 views

Improving Trimble GPS Pathfinder Office and TerraSync coordinate systems workflow?

We have GPS survey projects all over the country (CONUS and OCONUS) and I am wondering what the best practice is for having to deal with multiple coordinate systems. I can go from WGS84 UTM 18N meters ...
3
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1answer
274 views

Combining UTM zones into one solid map

I have an area, example 4000m x 4000m. So, 4x4km. The origin can be placed anywhere, maybe in center, maybe on the top-left, nevermind. Now, I want to fill this area with some stuff from OSM. I read ...
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1answer
396 views

ScaleLine shows NaN for LCC projection

I have used openlayers along with geoserver. My Map is having LCC projection by default, but SRS is EPSG:4042. The problem is that the scaleline shows NaN in meter as well as feet. How can I correct ...
2
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2answers
129 views

What's the accuracy of Web Mercator EPSG:3857?

Are there any references on the accuracy or (min/max/avg) error of Web Mercator when it comes to e.g. distance calculations? For the sake of completeness, I haven't found any reference to the ...
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1answer
27 views

Gall-Peters or other cylindric equal-area projections in QGIS?

Is it possible to use Gall-Peters or other cylindric equal-area projections like Hobo–Dyer in QGIS?
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0answers
22 views

Openlayer3: projection to Map.view coordinate system

I have an ol.layer.Tile with ol.source.BingMaps in epsg:3857 and I want add it to my ol.Map with projection 4258. The code below does that but when I display the layer it is rendered in the original ...
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2answers
277 views

Help, I have 10,000+ .shp files covering 3 UTM zones with unknown projections

I was handed a ton of property files with no projections attached but was told they are all in UTM zone 21S. Well once I merged them all together and projected them I realized that the data covers 3 ...
0
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1answer
20 views

Difference between MODIS sinusoidal and integerized sinusoidal grid

What are the differences between the MODIS sinusoidal and MODIS integerized sinusoidal grid? The sinusoidal grid seems to be currently used, whereas the integerized sinusoidal grid is marked obsolete (...
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0answers
38 views

Projection conversion issues; Philippines to OSM

I am working with some roads and bus routes data in Philippines. The bus routes data is in Philippines Zone 4: ESPG 3124 projection. I am trying to match it to roads data to generate stops at ...
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1answer
7k views

How to measure areas of features in OpenLayers plugin background maps correctly?

I can't figure out how to make areal calculations (eg. in km2). I have tried the 'field calculator', I have tried the 'measure area' function on the "attributes" toolbar, and i have tried fTools in ...
2
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2answers
63 views

Mistake in Calculating Area or a Bug in QGIS? [duplicate]

I am trying to calculate the area of a polygon following the step by step mentioned in all the questions related to this issues in this website. Nonetheless, the result of the area calculation is ...
3
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1answer
110 views

How to calculate the area of a polygon in a WGS84 Shapefile in QGIS?

I am using QGIS 2.12.3 Lyon and I want to calculate the area of my polygon in m2. For that I used the tool provided by QGIS, but the result is not as it should be. I got from QGIS 50 ha, while I got ...
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2answers
35 views

projection from epsg:4326 to epsg:4258

I'm looking for projection functions to convert coordinates in 4326 to coordinates in 4258 and viceversa. Any suggestions?
3
votes
2answers
64 views

What is wrong with my projection

I am using OpenLayers to plot a point on a map; the point should be located in the UK; but keeps appearing in the middle of the ocean (0,0). I have check my projection and I think this is correct. ...
0
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2answers
756 views

OpenLayers WMS - TypeError: this.resolutions is undefined

I'm trying to setup a map with WMS and WFS Layers by using Geoserver. However, when I'm combining WFS and WMS (with some Google basemaps) together in one map I got following error in Firebug: ...
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2answers
45 views

How can I find EPSG when it's not obvious from the .PRJ file?

Using Geoserver, I'm trying to get the correct projection for a map layer that is provided by the State of Idaho. I've tried looking up the EPSG code from http://prj2epsg.org/search. However, the ...
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1answer
23 views

Los Angeles county aerial imagery

I am looking for a basemap of LA county showing aerial imagery similar to google earth. However, I also need it in a specific projection: NAD_1983_StatePlane_California_V_FIPS_0405_Feet. Does anyone ...
20
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11answers
4k 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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0answers
37 views

Aligning layers in QGIS?

I am new at QGIS and am having a problem aligning layers. Possibly I just don't understand how projection works. I have 2 layers: 1) GPS waypoints collected in a GPS UTM zone 55N 2) polygon ...
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0answers
7 views

Requesting Mongodb collection with 2dsphere index from Leaflet LatLng

I am using projection and 2dsphere index. Similar posts have been done on mongodb support site but it may be a pure GIS problem,so here I am ^^. My scenario is the following : I create a Point/...
3
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3answers
15k views

Calculating projected area of polygons with field calculator in ArcMap?

I've got a polygon featurelayer in ArcMap 10. The coordinate system of the featurelayer's featureclass is web mercator. The dataframe of the map uses an equal-area projected coordinate system. I've ...
0
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1answer
208 views

How to get projection data (.prj) of raster image using GDAL/OGR?

I start with a boundary shape-file (think U.S. states) in lat/long that I convert to some projection, and then rasterize the result as a .tif. What I need now are the raster coordinates of the ...
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1answer
48 views

Don't understand error : Error in if (nchar(projargs) == 0) projargs <- as.character(NA) :

When I run two different scripts from examples (which seem to work where I took them from) I get an error in both cases. Something seems to be wrong in my general set up or something. But I have no ...
0
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1answer
18 views

CRS USA_Contiguous_Albers_Equal not working

I have selected the USA_Contiguous_Albers_Equal_Area_Conic, yet the map is showing a different projection. It worked when I started the project and something went wrong after I did a "print composer"....
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1answer
18 views

CRS different after r.reclass through QGIS different than source raster

According to the properties, my output raster is in a different projection than the input after running GRASS r.reclass through QGIS. Does anyone know if this is just a fluke and I can simply select a ...
3
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1answer
33 views

Configuring Project CRS to reflect degree coordinates

seems like this is a common problem, but posts with similiar questions did not solve my problem. I have close to zero GIS background so apologies for my ignorance. My goal is to extract only a ...
2
votes
1answer
46 views

Getting Borders as SVG using Peters Projection?

Is there a place where I can easily download the borders of all countries and continents as SVG using Peters Projection? Or what is the easiest way to get those? (I haven't installed anything on my ...
1
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1answer
41 views

How to tranform MODIS tiles into lat/long?

I'm trying to get the vegetation index nearest to a particular lat/long. I'm getting the data from here which is 250-meter spatial resolution hdf file. The globally gridded projection is split in 36 (...
0
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1answer
27 views

What SRS does leaflet use when it creates new markers?

I'm using leaflet 0.7. I'm wondering what spatial reference system is used when a new marker is created? Also, how does this impact my use of maps? (I'm using leaflet .7 because of dependency ...
0
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1answer
31 views

Projections leaflet and OSM

I downloaded data from OSM and extract lat/lng coordinates from a user who is clicking on a leaflet map. So my program returns the coordinates where a user clicked! I am wondering what crs I need to ...
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1answer
14 views

ENVI Changes the Projection of the output

After I have finished my Object-Oriented Classification, I open my result in ArcMap and I see that ENVI changed my Projection. Now the images are really in different places.
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0answers
43 views

Grib file information to create QGIS projection

I'm trying to create a specific projection with QGIS (something like that: +proj=lcc +lat_1=69.75 +lat_2=52.87 +lat_0=61.31 +lon_0=7.665 +x_0=0 +y_0=720 +ellps=GRS80 +units=m +no_defs). I have some ...
3
votes
1answer
42 views

Differences in the longitude and latitude between a LiDAR DSM and an optical image

I've downloaded the UK's LiDAR elevation data (see below) in laz format for a specific region (Tewkesbury) from: http://environment.data.gov.uk/ds/survey#/download From that, a DSM (Digital Surface ...
0
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1answer
2k views

Displaying a map in EPSG:26915 projection in open layers 3

My GIS experience is limited to having worked on several Geospatial Humanities projects. That is to say that I still struggle significantly with the technology (and terminology) in getting to my goal. ...
0
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1answer
30 views

Getting LonLat of a specific location in a specific projection on osm / google maps?

How can I get the coordinates in, for example EPSG:4326 of a specific location, in either OpenStreetMaps or Google Maps?
1
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1answer
33 views

How to interpret cell size arcgis

I have a raster layer that has cell size(x, y) 0.008928, 0.008928. I download it from the website as 1km resolution data under WGS_84. I can not find the unit for these numbers in the metadata. Is ...
1
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1answer
817 views

How can I project geojson borders on the google earth tiles in leaflet?

I started working with leaflet and google earth tiles. I want to add borders on my map so I tried to use the countries geoJson Data as a layer on the map. The problem is that the json borders ...
0
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0answers
17 views

How to resolve issue with model output in degrees and ASCII format cell size in meters when converting to a raster?

I am new to using Arc. I have data from a model output where each grid cell is 1/16 of a degree resolution. I have put the data into ASCII text format, however the header for ASCII under "cell size" ...
0
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1answer
30 views

Plot x,y coordinates on a Polyconic Map Projection

I have an image of a large polyconic map projection: (Note that the actual image is much larger, I just made it smaller to upload it.) I would like to take in a user's GPS coordinates and plot where ...
2
votes
2answers
497 views

Tiled raster image to be placed in an OSM/ Leaflet.js map

I have a mapoverlay in a custom projection which I need to add as a layer to an Openstreet map within a website. Since I was not able to change the projection earlier, I decided to manipulate the ...
15
votes
8answers
494 views

Seeking introductory texts about coordinate system projections?

Even after some time working in this GIS field, I still don't have a solid understanding of spatial references, how they are projected, and most importantly, if you still need to worry about the fact ...
0
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0answers
12 views

How to retrieve geodetic coordinates from a geotiff in Javascript?

I believe I have successfully calculated UV space coordinates by following this formula: var size = [image.getHeight(), image.getWidth()]; var xScale = directory....
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1answer
26 views

Soviet Maps projection

What was the projection used for the Soviet Topographic Maps? http://maps.vlasenko.net/smtm50/k-37-072-1.jpg i am trying to georeference a map from Georgia. I believe the projection used was GK (3 ...
6
votes
3answers
13k views

Using ArcMap, how may I convert a shapefile to use decimal degrees?

I have a shapefile that currently uses meters as the measure for its coordinate system, but the map framework I wish to use expects decimal degrees. I'd like to reproject my shapefile to use decimal ...
2
votes
1answer
641 views

How should I work with Layers with different projections in openlayers-3?

I'm using openlayers-3.8.2. I have some ol.layer.Tile layers and ol.layer.Vector layers. The projection of ol.layer.Tile layers and ol.layer.Vector layers are different. ol.layer.Tile layers work with ...
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0answers
11 views

Trouble Correctly Projecting from ETRS to UTM

Task is to project a DEM from ETRS_1989_UTM_Zone_30N to WGS 84 / UTM zone 29N. Easy enough right? Process succeeds, but inaccurately. I have recently read on this ESRI Geonet post that ArcDesktop ...