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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3
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2answers
91 views

Google layers not matching

I'm working in a project with whole Europe data. I'm working with WGS84 (4326), and sometimes I overlay my polygons with Google maps layer (in QGIS) to see some details. When I do this, I have to ...
20
votes
6answers
14k views

Defining projections for multiple shapefiles in ArcMap?

I have over 100 shape files that don't have .prj file and thus when I bring them into ArcMap 10 they show the coordinate system as unknown. I know all of the shape files coordinate system is GCS WGS ...
7
votes
1answer
144 views

What are the pros and cons of forcing square pixels on reprojection?

I am using Erdas Imagine 2014 to reproject 4-band raster data from GRS 1980 NAD83 Lambert Conformal Conic (ft) to UTM GRS 1980 NAD83 North UTM Zone 11 (m). Unlike ArcGIS, Erdas provides the option to ...
1
vote
1answer
53 views

Unable to save to in Geojson format with the correct projection

I have a shape file (Polygon) in Qgis that I wish to save in Geojson in order to display it with the mapbox javascript api. Original projection is in POSGAR 97 My issue is that it does not reproject ...
0
votes
0answers
56 views

Cause of MODIS Reprojection Tool errors?

I have installed the MODIS Reprojection Tool (mrt) and it says the installation completed successfully but it does not mosaic my images properly. However, there seems to be some projection errors. ...
1
vote
0answers
50 views

Arcmap: transform an image from Web Mercator Projection to Simple Cylindrical (Plate Carree) projection

I have an image that is projected using the Web Mercator projection. Does anybody know how to transform (in Arcmap) this image from the Web Mercator projection to the Simple Cylindrical (Plate Carree) ...
129
votes
12answers
31k views
1
vote
0answers
31 views

Vector seems to be only a pixel of a raster after reprojection

I have the South America hydro1k data for slopes and I am trying to extract the data using point sampling tool with a grid in Brazil's map. My problem is that, even though vector and raster seem to ...
2
votes
1answer
385 views

How to re-project the EASE (Equal Area Scalable Earth) grid with a ~25 km cylindrical projection to WGS84 0.25 degree?

I have nc files ,here is one file https://echange-fichiers.inra.fr/get?k=LUfqiyO1Dl7az5bihnS. from the metadata ,the projection is cylindrical and the resolution is 25 km: ...
2
votes
1answer
66 views

Misaligned GADM shapefiles and the NE dataset

I am very new to using GIS programs, so please excuse me if this is a trivial question. I'm having the following problem: When adding a GADM shapefile layer for Uganda onto the Natural Earth set of ...
22
votes
4answers
17k views

Layers with same coordinate system should align/overlap but do not?

I put 4 different layers into my ArcMap document, but only one of them will show up on the map! I should be seeing the other 3 layers as well. When I do a Zoom to layer, I can see one layer, but I ...
0
votes
1answer
49 views

Projecting INEGI shapefiles from Mexico - not lining up [duplicate]

I have two INEGI shapefiles from Mexico (2000 and 2010) that I want to line up with one another. The 2010 file projects in the right location and I would like the 2000 file to match/line up with the ...
1
vote
1answer
61 views

image rectification with Mercator projection

I have written an image rectification function which allows a user to select 2 points on an image and 2 points on a map. The function will then rectify the image so it is translated, scaled and ...
1
vote
1answer
57 views

How to find Latitudes and Longitudes of projections of the vertices of a rectangular plane below earth's surface? [closed]

I want to find out the latitudes and longitudes of projections of the vertices of a rectangular plane inside the earth's surface. I know dimensions of rectangle, angles of orientation and latitude and ...
1
vote
2answers
67 views

Accurate local map projections

Is there a map projection that can accurately represent reality at a local area, i.e. when transforming the map could I choose an area that I care about accuracy and allow distortions elsewhere? Like ...
1
vote
1answer
87 views

6 degree to 3 degree Transverse Mercator transformation

I am looking to plot coordinates that were given to me but I am having some issues projections. I currently have my data projected to NAD83 MTM 1, but the coordinates that were given to me are based ...
2
votes
0answers
72 views

Difference between feature to raster and polygon to raster

(I'm using Arc 10.1) I'm trying to rasterize a data set. I have a shapefile with geographic coordinates (GCS_GDA_1994) which I want to convert to a raster with 100m grid cells. So I need to project ...
1
vote
1answer
69 views

Shapefile not projecting correctly [duplicate]

I am still new to this, so I apologise if I don't make a lot of sense! I am using QGIS 2.4.0 Chugiak. I am working on a project set to the GDA94/MGA Zone 50 coordinate system with 'on the fly ...
2
votes
1answer
45 views

Error reading large virtual raster with rasterio: “Cannot invert degenerate transform”

I've created a virtual raster using gdalbuildvrt, which covers a large extent (England) at a high resolution. The data is fairly sparse, focused around the coastlines with no files covering inland ...
1
vote
3answers
2k views

How to convert projection

I got sample shape files with the following *prj file content: ...
1
vote
0answers
65 views

Google Map Projection Skew - Need correct Projection

I'm having a really difficult time resolving skewed grids when projecting onto Google maps using Alteryx outputs. Within the module, I'm taking GRD files and aggregating rows and columns to re-size ...
0
votes
0answers
58 views

Understanding X Y coordinates: geocode before or after projecting? What determines how many decimal places?

I am trying to figure out how different my groups' past Network Analyst analyses have been because they were using a geographic instead of projected coordinate system. But I'm getting hung up on the X ...
2
votes
1answer
30 views

Figuring out what coordinates supposedly using 'NAD31 projection' refer to

I'm working with a GeoJSON file that contains sets of coordinates associated with street corners in the city of Montreal, Canada. The spec sheet of the API delivering those GeoJSON specifies that the ...
2
votes
1answer
88 views

Why is this .prj file causing the shapefile to render in meters instead degrees?

So I've got a shapefile that has polygons of countries, with coordinates in decimal degrees: Country (String) = Algeria POLYGON ((6.928073999999953 36.88360652, 6.949973999999969 ...
2
votes
1answer
142 views

How to find the projection of an image?

Instead of georeferencing the image and deforming it, I'm trying to find the projection used by the author of the image. I've got tens of these distribution maps to digitize. The idea is to avoid ...
1
vote
1answer
42 views

Determining projection of Texas county shapefile?

I have a Shapefile of San Jacinto County in Texas. It thinks it is NAD83 UTM Zone 15N, but the dataset isn't jiving with any other dataset. Max X: 1,073,721 Max Y: 11,223,970 Min X: 895,728 ...
1
vote
0answers
36 views

Question about projected coordinate systems 30m DEM for Contiguous US

What is the best Projected Coordinate System (PCS) for the contiguous US (whole, not parts) if I want to maintain distance and area accuracy as much as possible across a nationwide DEM dataset? I'm ...
0
votes
1answer
559 views

How to create a custom projection of PRS92 and UTM 51N for the Philippines? [duplicate]

Possible Duplicate: How to define new custom projections in QGIS? How do I create a customized CRS parameter in quantum GIS? I'm try to create a projection of PRS92 and UTM 51N. This ...
2
votes
1answer
127 views

gdal2tiles generates small picture inside 256x256 tile

I've used gdal2tiles for generating tiles in number of different polar projections and always experienced the same problem — strange small picture inside normal 256x256 png with the rest of space ...
2
votes
1answer
94 views

Defining projection, reprojecting, and wrong area values [duplicate]

Apologies for duplication--this was mentioned in a previous post, but was suggested that this specific problem should be posted separately. My data: http://water.usgs.gov/GIS/dsdl/aquifrp025.tar.gz ...
0
votes
1answer
56 views

Cannot obtain correct area values *With* correct projections

I'm trying to get the percentage of each U.S. county overlaying groundwater (data from the census and USGS respectively). They're both polygons. I have 1) correctly projected the data and the layer ...
0
votes
0answers
53 views

Is it possible to rotate the geographic projection in QGIS?

I'm trying to create a Qgis plugin that can rotate a raster layer in the canvas so that the north is pointing at another direction. Unlike the thread below, I'm open to defining a custom projection. ...
1
vote
1answer
30 views

XY data --> NAD_1983_2011_California_Teale_Albers always fails?

In ArcGIS 10.2, I am importing XY (point) data from excel, and have been having trouble projecting it into the following Projected Coordinate System: NAD_1983_2011_California_Teale_Albers -- NAD ...
1
vote
1answer
78 views

Projecting INEGI shapefiles from Mexico

I have two INEGI files from Mexico (1990 and 2010) that I want to use the same projection. The 2010 file works fine (see below) and I would like the 1990 file to match the 2010 one. The shapefiles are ...
3
votes
1answer
100 views

Projection mismatch when plotting precipitation with ggplot

I'm trying to plot accumulated precipitation in Brazil for a given period, see code below: Load packages library(raincpc) library(SDMTools) library(raster) library(ggplot2) library(rgdal) ...
0
votes
0answers
33 views

What projected coordinate system to use for whole of USA? [duplicate]

I need to determine a projected coordinate system for a wide area that exceeds more than one zone? For Example: If I want to give US a UTM projection which zone will be represent the whole US? ...
0
votes
2answers
168 views

Projection problem? — OpenLayers, Drupal, and MapBox

I've installed OpenLayers in Drupal 7 and created a view that pulls geofield data for a "Geography" vocabulary (states, tribes, and U.S. jurisdictions) and shows points on a map that I'm storing on ...
0
votes
1answer
41 views

Drawn figure looks stretched

I have written some code which offset a certain latitude and longitude with a distance in centimeters. What I am trying to do is based on a coordinate and a vector create two new points along the line ...
0
votes
0answers
38 views

Euclidean Distance Function performed on unprojected data

I am looking to perform a simple multi-criteria analysis on a data set comprised of two criterion: occurence of wildfires and road accessibility. First, the project CRS was enabled with "on the fly" ...
0
votes
2answers
54 views

OpenLayers + Geoserver problem with wfs projection

In geoserver i have a layer in EPSG:26191. In OpenLayers i add it on map as WFS: markerLayer = new OpenLayers.Layer.Vector('Markers',{ strategies: [new OpenLayers.Strategy.Fixed()], ...
0
votes
1answer
79 views

QGIS to solve projection mystery in Postgresql

I downloaded some data from local agency. Per QGIS 2.2, I defined the projection to 'EPSG:3587 - NAD83(NSRS2007) / Michigan Central' in postgresql (maybe ArcMap). Data is in Postgresql 9.3. I am ...
1
vote
2answers
161 views

Wherer is wrong with transforming a WGS84 [lon,lat] point onto google maps

I want to convert a longitude latitude point in WGS84 coordinate system to Google Maps(not google earth) coordinate, But when I put the converted point on google map, it always has a roughly 10km ...
0
votes
1answer
53 views

which Coordinate system should I use for 3D analysis?

I am creating 3D surface below the earth's surface using ArcGIS and then I need to find distances to the plane from the surface. Which coordinate system shall I use? 3D interfaces like IProximity3D ...
1
vote
0answers
53 views

Why can't I reproject from HARN State Plane Ft Intl to State Plane Ft?

I'm attempting to reproject a feature class that is: NAD_1983_HARN_StatePlane_Oregon_North_FIPS_3601_Feet_Intl to our standard, which is: NAD_1983_StatePlane_Oregon_North_FIPS_3601_Feet When I ...
1
vote
2answers
73 views

Projection for polygon intersection confined into one hemisphere?

I have polygons where each vertex is a (lon,lat) geographic coordinate. I want to find out if they intersect or contain each other. The polygons are guaranteed to never exceed a hemisphere (so they'll ...
4
votes
1answer
103 views

What's the correct way to reproject a population raster?

I'm working with a population raster that is in the WGS84 coordinate system, and I want to get it into a projected coordinate system (Albers Equal Area), using ArcGIS 10.1. According to the metadata, ...
1
vote
0answers
33 views

Geodjango transform introduces large errors

Apologies for the possibly naive question. I'm trying to understand how Geodjango (running on PostGIS) deals with coordinate transformations, and am experiencing some unusual behaviour. Let's say I ...
2
votes
1answer
49 views

Geoserver projection recognize problem

I'm publishing shape files in geoserver through curl,my problem is that geoserver didn't recognizing the projection which is in ESRI WKT format(layer was publishing).I searched for this problem i ...
0
votes
0answers
147 views

Fixing Mapinfo export to Google Earth projection which is slightly off?

I have around 20 layers of data (points and polylines) in Mapinfo TAB files which I need to export to KML files, however the projection is slightly out. I have tried various different projection ...
18
votes
8answers
17k views

How do I convert State Plane coordinates to latitude-longitude?

Given a specific state plane coordinate system (whether NAD27 or NAD83), are there any resources to convert to latitude-longitude?