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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50 views

Transforming lat and long to Mercator x and y

I've been trying to plot a set of lat and long coordinates to a Mercator map using the following set of equations; x = long - long0 y = ln(tan(pi/4 + lat/2)) These equations are from a page on ...
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3answers
165 views

Area units for output polygon in WGS 84 UTM Zone 32N using QGIS

I am calculating the area of my polygon and I have used WGS 84 UTM zone 32N to calculate the area (using geometry on the field calculator) of my polygon, and I obtained 745461 (without units). How ...
6
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2answers
77 views

Inferring lat/lon based on known location coordinates

I have a point dataset with a set of coordinates that is in an unknown projection. For some of these points I know the unprojected latitude and longitude. Based on these known data points, would it be ...
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2answers
129 views

Inaccurate Buffer Distances

When buffering a point, the result is inaccurate to the basemap. I specify a 200 foot buffer around a point however the resulting buffer has a distance from the point of about 260 feet. Both the ...
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1answer
38 views

Alternative to Web Mercator projection that does not look too small on phone?

My issue with Web Mercator as a projection to use online is that I think it gives people an unrealistic perception of space. Greenland looking massive is a good example. One benefit of Web Mercator, ...
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1answer
82 views

Shift in the data between CartoDB and stamen layer, Google Maps API

I have a geojson loaded into CartoDB database. And I have a CSV file too. Names field would be common in both the GeoJSON and CSV file. I had written a logic if the place name in CSV matches the place ...
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1answer
65 views

Polygon Surface Area Calculator in different map projection(s)

I'm simply looking for an online tool or a utility to calculate the surface area of the same polygon (i.e shapefile) in different projection (projected and geographic projection system) systems. It ...
3
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1answer
87 views

What is the real distance between positions?

I'm trying to figure out what gives me the most accurate distance between positions: Measuring distance directly (using Geod.inv)? Measuring distance in 2D (after transforming to a known projected ...
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42 views

Choosing projection for routes that fall within two UTM zones? [duplicate]

I'm creating charts for routes that fall within two UTM zones; 30S and 31S. The offshore routes are in the Alboran / Balearic Sea - connecting Spain to Algeria. What projection should I use?
3
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2answers
122 views

What is a suitable map projection for the entire state of Idaho?

I am working with some sample GIS data for Idaho. The data is in geographic coordinates but I want it in projected coordinates. I am unsure how to address the issue of projection as Idaho crosses ...
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1answer
32 views

Using map units to define radius of point feature in styles in QGIS: not getting it right

I have a point feature in a map which is in EPSG32723 (WGS84 - UTM zone 23s) and I need to style it as follows: A center point in red and a circle below it which has a particular size in meters. I ...
3
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0answers
55 views

Wrong area using Albers Equal Area Projection in GRASS for Java, Indonesia

I am just getting to know GRASS 7.0 and I am struggling finding a good projection to work on a spatial analysis of Java, Indonesia. I am new to the forum, so if information's are missing for a better ...
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2answers
198 views

are these two proj4 utm projection strings equivalent?

I have a list of proj4 calls. Some of them have one format and some have another, I've been told they are equivalent. Is that so? If so, which one should I use? for example, for ETRS89 / UTM zone 20N:...
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1answer
40 views

Projection of WMS in MapInfo

I am using the OSM open Roads WMS layer that comes included with MapInfo. I have noticed that when I load this layer the projection of the Map window changes to 'Popular Visualization CRS.' All the ...
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0answers
5 views

The effect of setting the reference system as “Unknown” when building stereo block

I couldn't figure out what is the effect of setting the reference system as “Unknown” when building stereo block in Erdas.
3
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1answer
21 views

GCS and PCS data misalignment in ArcMap when zoomed in

I have a shapefile in NAD83 UTM18 which I need to get into GCS NAD83. I tried both loading it into an empty GCS NAD83 feature class directly and the "project" tool. The results are the same - the ...
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0answers
56 views

Projection Issues - OpenLayers / MapServer / NAD83 State Plane FT

I am having projection issues with OpenLayers version 2.13 with MapServer and the Proj4 library. Pulling layers in NAD83 State Plane Feet projections on top of an OSM or MapQuest Base Map in Google ...
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1answer
41 views

Importing ESRI:102091 Monte Mario reference system

I am trying to import a dataset generated by my local council (Turin, Italy). The data appears on the map but it's slightly shifted and it doesn't match the Open Street map layer that CartoDB uses ...
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0answers
39 views

Converting coordinate obtained from google maps to be used with gdal_translate in java or cs2cs?

this is a follow on question from Geo-Referencing an image from google maps with gdal_translate I am trying to get cs2cs to work but I am getting the following error. My command is as follows: ...
3
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1answer
67 views

Geo-Referencing an image from google maps with gdal_translate

I am trying to geo-reference an image using gdal_translate in a command prompt. Currently I have the following gdal_translate.exe -of GTiff -a_nodata 0 --config GDAL_DATA "Config location" -a_ullr -...
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1answer
206 views

Transform an image with projection EPSG:4326 to EPSG:3857

I have an image with known boundary and projection EPSG:4326 and want to overlay it to openstreetmap using Leaflet.js. I have tried using function imageoverlay, but the image is not aligned with the ...
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36 views

getting started designing satellite projection raster

How do I get started designing a map with a satellite projection like this:http://bl.ocks.org/joyrexus/6619251. So far using d3 I've created a map of North Africa w/ topojson and tiles from Mapbox but ...
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65 views

d3.js Projection for Washington DC area

I'm making a small thematic map of the Washington DC area using d3.js. Everything I've tried "tilts" the square of DC. Is there a d3 projection that will put DC at the right angle? https://github....
2
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1answer
109 views

Map scale factor when converting from Mercator to Equirectangular

Lets say I have a map in Mercator projection, and I know top and bottom latitudes: topLatitude = 80; bottomLatitude = -55; I also know width and height of a map: width = 800; height = 500; I want ...
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1answer
62 views

Define Projections for layers with multiple locations in MXD's

# Script to use Layers in MXD source file paths to locate and redefine projections import arcpy, glob, os, sys, arcgisscripting mxd = arcpy.mapping.MapDocument("N:\MXDs\_ThomaKL\MXD GPS Valves\...
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1answer
194 views

How to overlay Image to openstreetmap using leaflet.js

I want to overlay a wide range satellite image onto openstreetmap using leaflet.js. The satellite image is in Equidistant Cylindrical Projection. This is how I initiate the layer. L.imageOverlay(...
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2answers
70 views

Redefining point shapefiles in MXD that have no projection and are located in different folders using ArcPy?

# Script to use Layers in MXD source file paths to locate and redefine projections import arcpy, glob, os, sys, arcgisscripting from arcpy import env, mapping path = os.getcwd() env.workspace = path ...
3
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2answers
55 views

Alaska Series E projection in ArcGIS for Desktop?

I am trying to digitize a scanned map that appears to be in the Alaska Series E projection. I have also seen this referred to as Modified Transverse Mercator. While this projection is listed as ...
8
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2answers
251 views

Convert a geotiff web-mercator into an azimuthal equidistant projection

I have a geo-referenced tiff file, in the web-mercator projection; and I need it converted to an azimuthal equidistant projection. I'm new to GIS and can't figure out how to do this. I'm open to ...
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2answers
65 views

Displace Lat/Long by meters

Sorry for the inflammatory title, Yes, I know these cannot be added. Problem: I have a vehicle that is reporting LL84, coordinates. It has a sensor that reports footprints of obstacles (LineString, ...
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0answers
67 views

Getting same results from Mapping toolbox of MATLAB as ArcMap?

I am newbie in GEO. I have a point [lat,lon] = [-77.5100 , 166.4000]. I want to find its projection based on equidistant Azimuthal projection method. When I use ArcMap 10.3.1 (with default parameters),...
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1answer
72 views

How to make two layers with different CRS line up correctly?

I have an Excel Table with Lat/Long information. Its lat/long of this coordinate System: UTM zone 29n My population density map instead is this coordinate system: UTM WGS84 Example: Barcleyville: ...
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1answer
385 views

Open Layers 3, GeoJson EPSG:4326

I have two layers: 1) var layer = new ol.layer.Tile({source: new ol.source.OSM()}); 2) var layer_g=new ol.layer.Vector({ projection : 'EPSG:4326', style: new ol.style.Style( { ...
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0answers
149 views

Transforming zonal and meridional velocity from regular lat lon to rotated lat lon?

Like in Transforming regular lat/lon to rotated lat/lon? that was asked before, I am working with climate data and I need to transform zonal and meridional velocities (u and v) from regular lat lon ...
1
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1answer
351 views

stack rasters with different extent and resolution in a loop with R package raster

I would like to stack rasters with the R package "raster". Layers are in ascii format. I want to crop them to have the same extent and project them to have the same resolution. My code gives raster ...
3
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2answers
83 views

What kind of projection is this?

Can someone tell me what the projection is in this zone map from NOAA? I am trying to replicate it (or get close) in QGIS.
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0answers
40 views

Creating equirectangular projection from 3d spatial model?

Apologies if this is not the right group for this question, but I think there may be people here who can help. (I'm open to suggestions for better places to ask.) I have a program that contains a ...
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0answers
14 views

MapInfo2leafletjs tool

I've downloaded a tool to export a table from MapInfo GIS to leafletjs. The base map from Openstreetmap has been created, but the choropleth map of regions is not being displayed. One possible ...
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0answers
45 views

Correctness of Measurement

I tried Google, but the questions isn't that easy to put in Google, so I haven't found anything about this. I am making a database with different locations (latitude and longitude). For this I have ...
0
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2answers
273 views

Displaying X, Y coordinates on ArcGIS not working

I am trying to geocode some coordinates I have from my Excel sheet onto ArcGIS but everytime I do so, it doesn't show up on the screen. When I right click on the sheet layer to see where it went, it ...
2
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0answers
45 views

How can I move a polygon to a different place on the globe, while maintaining its true geographical size? (QGIS)

I'm trying to do something similar to the Greenland vs Africa comparison -- superimpose one country over another, showing how their true sizes compare (the example on the right). Thought this would ...
2
votes
0answers
73 views

Changing projection on each page of data driven pages

I am working with data driven pages and a raster image of the world. I have a separate polygon shapefile of all of the UTM zones (with a polygon for zones 1-60, north and south, for a total of 120 ...
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1answer
76 views

Defining Projection Lambert Conformal Conical w custom GCS

I have a shape file from Mexico´s INEGI site that doesn´t have prj file. I am having trouble defining the projection in Arc. INEGI tells me it is projected as Lambert Conformal Conical with a ITRF92 ...
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0answers
27 views

Measuring large distances when all layers are in decimal degrees using QGIS?

I just developed a distance matrix between various points across Canada in QGIS. The distances produced are in decimal degrees, and I would like to view them in metric. I am unsure how to do this.
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0answers
94 views

gdalwarp UTM Zone 1 to WGS84 - fails to transform

I have a global dataset consisting of tiles in UTM projection that I want to mosaic and therefore need to reproject to a common projection. Can I solve my reprojection error with options to gdalwarp ...
0
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0answers
23 views

What is the right projection for area calculation in Kenya? [duplicate]

I want to calculate the area of counties (1st admin level) in Kenya in ArcGIS. What is the right projection for that? I know I should use an equal area projection, but when I use them (I tried six ...
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2answers
49 views

Geoprocessing results outside of defined extent [closed]

I am running ArcGIS 10.2 Desktop Several different models I have built and tested successfully previously are demonstrating the same problem. They appear to execute slightly to the South of the ...
0
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1answer
503 views

OpenLayers 3 display wfs EPSG:4326 on EPSG:3857 map

Is it possible in OpenLayers 3 to project an EPSG:4326 wfs vector layer on to say a MapQuest EPSG:3857 map? I've tried the following code (modifying this example Open Layers 3 wfs example, but the ...
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1answer
350 views

Openlayers3 using custom EPSG:25832

I want to use EPSG:25832 as the default projection for all my layers. The projection is not working correctly because the Position (center point) should be in Germany but I end up in France. When I ...
3
votes
2answers
226 views

Ukrainian topographic map: projection and coordinates?

I need some help. I managed to get Ukrainian topographic maps for my project. I'd like to do the georeferencing in QGIS. The problem is that I don't have a clue what projection was used and how to ...