A map projection is any method of representing the surface of a sphere or other three-dimensional body on a plane

learn more… | top users | synonyms (1)

2
votes
4answers
4k views

Export to new projection in QGIS 1.7

Suppose I have layers A and B. I don't know their projections but by the looks of the map I know they are not the same. In QGIS 1.6 I would use one of my favorite features: Vector> Data ...
1
vote
1answer
88 views

cannot get EPSG of bounding box

I use openlayers 2.12. I created a form where the user can insert a bounding box, to insert to the database a new borough. To check the EPSG of the borough I tried the following //ba bb bc bd came ...
3
votes
1answer
174 views

Problem with projection in layer

I'm having problems with visualizing a layer which is in EPSG:4326 Apparently the geometry looks perfect, but I don't know why, it's not in real coordinates. I have projected it to 4326 with QGIS, ...
0
votes
2answers
1k views

Appropriate map projection for the UK?

As the title: what is the most appropriate projection to reduce distortion, if I'm just showing the UK on a map? Is WGS84 fine (since it's a relatively small area), or should I use some other kind ...
2
votes
1answer
176 views

How to reproject EPSG:102218 with QGIS?

I have a raster file. ArcMap says it is in NAD_1983_USFS_R6_Albers (EPSG:102218). QGIS says it is in USER:100000 - * Generated CRS (+proj=aea +lat_1=43 +lat_2=48 +lat_0=34 +lon_0=-120 +x_0=600000 ...
6
votes
2answers
92 views

Define projection at the record level

Hopefully this isn't too dumb a question, but is it possible to define projection at the record level, instead of a whole layer or table? I want to create a "project" database for all the work my ...
2
votes
0answers
20 views

Draw cirlcle on Equirectangular projection [duplicate]

I'm trying to draw a circle (actually a great circle) on an equirectangular map to archive something like this http://i.stack.imgur.com/7EliU.png (from here). So I have the lat/lon coordinates of the ...
2
votes
1answer
1k views

GeoTools and PostGIS with ESPG:3857

I'm trying to use both PostGIS and GeoTools with the same ESPG:3857 projection, however, it looks like the projections in PostGIS and GeoTools differ. This is what I have in PostGIS: PROJCS["WGS 84 ...
5
votes
1answer
171 views

Good projection for covering most of the world

I'm writing an application for building navigation routes thru the city streets, and not quite sure what projection would be best. I tried EPSG:3587, however, the tools I'm using - GeoTools and ...
1
vote
1answer
81 views
3
votes
2answers
596 views

Partial Map Pixel Projections

I have the following: A PNG or JPG of a random width and height, in pixels, that represents a partial map of the world (i.e. a rectangle of the United States). The four corners of this image are ...
3
votes
2answers
621 views

Geostationary Satellite Projection

What is the equation needed for forward and inverse transformation of Geostationary Satellite projection.?. How to convert it to Geodetic and vice versa. Geostationary satellite projection is ...
1
vote
0answers
352 views

Incorrect coordinates when reprojecting NAD27 to NAD83

I have some historic UTM coordinates as NAD27 (556787, 7169250) which I entered into a spreadsheet and have imported into QGIS. I assign them the projection Nad27 / UTM zone 12N (EPSG: 26712) I ...
3
votes
1answer
145 views

Rhombus shaped pixels when viewing an image referenced in WGS84

Following the Question What is the projection of WGS84 in GIS software?, in the comments section of the answer http://gis.stackexchange.com/a/73578/5256, Jake very well explains that Because the ...
2
votes
2answers
286 views

Mapping elements in a warehouse

I am new to GIS. For a small project I want to map elements in a warehouse and want to find the location of the elements later (e.g. nails are located at x,y). Now I am wondering what kind of ...
1
vote
1answer
444 views

Change projection system .tif file [duplicate]

I have a list of .tif files which have the wrong projection system (NAD_1983_UTM_Zone_13N). However, I want to have those files in (WGS_1984). I want to do this by a script that can transform tif ...
3
votes
1answer
921 views

How to render area that crosses 180°?

The problem is that the Chukotka Peninsula is located in the Western Hemisphere. So it is on the left side of Natural Earth Datasets. It needs to be moved to the right. I tried to use following ...
1
vote
2answers
461 views

Shapefile point coordinates to lonlat

I'm currently trying to parse a shapefile (http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf) with c++. While I have no problems parsing all the data I need, there is a problem with the ...
1
vote
2answers
450 views

Using a different projection to calculate areas using the Field Calculator

I have a dataset that is in a WGS84_UTM projected coordinate system, can I force the Field Calculator to use another coordinate system when I use it to calculate areas using pythons ...
2
votes
2answers
1k views

Suitable projection for a map of Japan

I'm making a map of Japan in QGIS which will span UTM zones 54 and a small part of zone 53 (central and North Honshu). I'm using Natural Earth raster and shape file datasets with some WSG84 based ...
7
votes
3answers
1k views

How does ArcGIS determine which transformation to use when projecting on the fly?

How does ArcGIS determine which transformation to use when projecting on the fly? Where this would come in would be going from NAD 83 to WGS 84. Multiple transformations could be considered so how is ...
3
votes
2answers
144 views

How to fix Raster Dataset with numbers in Extent that look like latitude/longuitude but say metres?

In ArcGIS for Desktop 10.1, the Spatial Reference of my Raster Dataset reports that its units are metres (well meters) but the values look like decimal degrees e.g. -33 degrees is highly plausible but ...
2
votes
1answer
3k views

Canvas Units to Degrees, Minutes, Seconds

I am using the WGS 84/UTM coordinate sysytem. When I go to > Project Properties / General / Canvas Units to Degrees, Minutes, Seconds my coordinates are wrong. I am using QGIS 2.0.1
3
votes
2answers
713 views

Is there a world projection that looks like a 3D globe?

I would like to try and show data such that it appears as if it was on google earth. For example, in this case, the view of the earth is circular-like and the data shown curves around. Are there any ...
2
votes
2answers
1k views

albers projection to Lat, Lon

Thanks in advance for helping me with my issue. This GIS stuff is using parts of my brain that have remained idle since high school, and some parts are working faster than others. I have land data ...
6
votes
2answers
1k views

Are there tools in ArcGIS for drawing compass bearings, and which projection should be used to create a map showing them?

I have a requirement to create a map (or multiple maps) showing four different locations with a bearing compass drawn around each one, oriented towards Grid North. I was told that each of the ...
2
votes
1answer
128 views

Why does same image in two ArcGIS ArcMap configurations show different extent numbers?

I would like to get hear from you about the situation I am seeing here. What It got my eye was that when I download an ASTER from Reverb/ Echo from USGS website. At work, I load my ASTER file to my ...
12
votes
2answers
2k views

How can I make a polyline wrap around the world?

I am using leaflet maps to create a representation of a round-the-world challenge. I would like to add a polyline which heads east from tokyo and then appears west of south america on the map - but ...
3
votes
3answers
15k views

Calculate projected area of polygons with field calculator in ArcMap 10

I've got a polygon featurelayer in arcmap. 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
votes
1answer
1k views

GCS_WGS_1984 and 900913. What is the difference?

I use WMS Service with mymapproxy/mapproxy.yaml : services: demo: kml: tms: wmts: wms: srs: ['EPSG:4326', 'EPSG:900913'] md: title: MapProxy OSM WMS Proxy abstract: This ...
0
votes
1answer
300 views

Problem in calculating length

I am Digitizing road line in India using open layer plugin.When I calculate the length of line using field calculator it gives me the result in millimeter . I thought it is the projection problem and ...
0
votes
1answer
2k views

Point shapefile is not displaying.

I have created a point shapefile in ArcGIS 10.0 that has a geographic projection, but it will not display/draw. When I view the properties it has no "extent" information. Is this the problem? Thanks ...
1
vote
1answer
166 views

Raster Dataset projection problem

I have a problem connected with my Raster Dataset projection. Two of its bands cannot be shown in some scale - only under 1:1500, when I use 'Zoom to raster resolution' option. Histograms for all 3 ...
2
votes
1answer
772 views

Map projection lat, lon to pixel?

I'm trying to find the concave hull of a lat, lon pointset but when I project my points on my map it doesn't look like expected. I've tried a lineare projection and a spherical projection. My data is ...
3
votes
2answers
4k views

which is the suitable Geographical Coordinate System and Projected Coordinate System for India

I want to create a spatial data for entire India, usually I use WGS84 as GCS and UTM zones for PCS in the places in India, but when I have to create the spatial data for entire India, I get confuse ...
4
votes
1answer
472 views

D3 to match this QGIS projection?

I have a map of Finland in QGIS, which says CRS = ETRS89 / ETRS-TM35 (Authority ID = EPSG:3047). I'm trying to show the map with D3, and can't quite match the borders/projection. The black one is ...
2
votes
2answers
302 views

Distance between latlongs varies in different projection systems?

I have shapefiles with correct projections. The SRS is EPSG 32735 (WGS 1984 UTM 35S) Now, I have these two coordinates from this projection system: (31.3751,-23.4388) and (31.3779,-23.4355). ...
1
vote
2answers
1k views

MMQGIS: How to make grid layer in meters not degrees?

I've read several of the posts on here pertaining to MMQGIS Create Grid Layer option, but I have not found information on how to make the grid based on meters veres degrees. I know how to manipulate ...
1
vote
0answers
584 views

ArcGIS / ArcMap problem with tiff file and projection

I have a raster in ArcMap . The projection is WGS 1984 UTM 22. When I look the details of the projection I can see that the "scale factor" is 0.9996 When I save this raster in a in tif file and the ...
1
vote
2answers
310 views

will ogr get coordinates in geographic coordinate system or projected coordinate system when using getPoint(int,OGRPoint*)

Consider the code that I have written in the stackoverflow question How to extract vertexes of geometries in ESRI shapefiles using ogr library with c++, I have used the code to show shapefiles on an ...
2
votes
0answers
38 views

Differences between points and lines as poles in an equal area projection

I am planning on using an equal area projection in a current project. I used this website to determine which projection I should be using. I hadn't previously considered it, and was wondering if ...
2
votes
0answers
96 views

Recommendations on universal projection API or algorithm for ArcObjects?

As asked on the esri forum here, we are trying to convert a geometry from any spatial reference to any other spatial reference. We have tried the default IGeometry.Project(target_spatial_reference) ...
1
vote
2answers
631 views

How to add new projection using ArcObjects of ArcGIS for Desktop?

I want to use "Mars MOLA" { 86 3396000.0 3396000.0 "Mars MOLA" 0 0 0 0 0 0 0 } with my shapefiles.
1
vote
1answer
657 views

What's the correct transformation for Lambert Conformal Conic for Mexico?

I have a shp archive without the .prj file. I don´t know the proyection of this shp, but I think it is in lambert conformal conic. Can anybody helpme to proyect this shp? i´ve tried to proyect it in ...
1
vote
0answers
209 views

Am I correctly projecting a geometry using a WKID in ArcObjects?

I would like to take in any valid WKID for a spatial reference and then project a single geometry to it. The following code seems to be working, but (1.) can someone verify that this is the correct ...
2
votes
1answer
387 views

QGIS Georeferencer, unexpected transformation, and GCP placement

Im trying to get the sample map which i believe to be EPSG:3112 into QGIS and geo referenced. In my screenshot, on the right is the raster in georeferencer with the points i have added. On the left is ...
0
votes
1answer
189 views

Mapguide and OpenLayers SRS WKT

I am trying to create OpenLayers vector features based on WKT strings that I retrieve from a MapGuide server. I have successfully gotten the proper geometry to be rendered, but I do not know how to ...
8
votes
2answers
1k 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 ...
1
vote
0answers
582 views

Help me convert this US Lambert Conformal Conic Google Maps Projection to Australia

Following on from this question: Identify what projection this Australian map uses? <- this is the sort of map i want to load in I need help changing the bits necessary in this example of Lambert ...
2
votes
0answers
2k views

How do I change from lat/long to a metric coordinate system in GRASS?

Yes, it's yet another transformation question. I am working with ASTER DEM data, which is LatLong WGS84. I want to process the DEM map into an STL file for use in a CFD simulation. The script I am ...