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)

32
votes
2answers
2k views

What coordinate system should be used to store geography data for celestial coordinates?

I am doing an astronomy project. I want to have the information about our images stored in a spatially enabled database. This, I would think, should be a very easy special case for GIS functions ...
7
votes
1answer
616 views

Determining Natural Origin for a GeoTIFF file (Lambert Conic)

I am trying to display an existing GeoTIFF file (from the FAA WAC set) in an application that requires the GeoTIFF NaturalOriginLongitude tag (FalconView 5.1.1). There are some older files in that set ...
0
votes
0answers
20 views

Geographic projection for ASCAT metop-a product

I have an ascat bufr over souther south America and I need to project raster data over a map. What is the right projection for this product? I'm lost with this options: ortho, mercator and ...
15
votes
2answers
704 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 ...
3
votes
1answer
443 views

USGS GeoTiff extent via GDAL

I have 2006 land cover GeoTiff from the USGS site (for a county in VA, USA). The projection is Albers Conical Equal Area Units. The download came with an HTML metadata file that tells me the geo ...
3
votes
2answers
119 views

Which SRIDs to use for what tasks?

I try to understand the idea behind the different Spatial Reference Identifiers. I understand that the different SRIDs identify different projection views on the earth and that they are important for ...
0
votes
1answer
81 views

Use lamber 93 imageOverlay with leaflet on top of OSM tiles layer

I'm trying to use a lambert 93 image overlay on top of an Open Street Map title layer. var map = L.map('map'); L.tileLayer('http://{s}.tile.osm.org/{z}/{x}/{y}.png', { }).addTo(map); var coords = { ...
3
votes
1answer
42 views

What projection is this?

Can anyone figure out this projection? Eckert III looks close but is not quite right.
5
votes
2answers
141 views

Coordinate/projection system issue in ArcGis 10.3

I am new in this community and I am also a new user of ArcMap. I am facing a problem, my shapefiles are in a GCS WGS 1984 and I have to add a new shape file that is in a projected coordinate system ...
1
vote
0answers
22 views

Sinusoidal Projection and ArcInfo Sphere Datum Woes

I am using published forest loss data (found here: http://glad.geog.umd.edu/indonesia/data2014/index.html) that uses the ArcInfo Sphere datum with a sinusoidal projection. I am seeking to transform a ...
1
vote
1answer
70 views

Understanding precision of ArcGIS geodatabases?

I would like to know how precision is handled in ArcGIS software. Is it using a real Computer Algebra System engine, an arbitrary precision library or do others tricks to handle precision ?
3
votes
3answers
2k views

Why are the tile coordinates different in Google maps and Google earth?

I have a .NET application that typically uses the standard Google Maps JavaScript API V2. Within this application I am using a GTileLayerOverlay to add my own custom dynamic tile layer. function ...
4
votes
2answers
237 views

Map projection process for three-dimensional point cloud

I have some points given in ECEF coordinates (or LatLongAltitude based on WGS84, which is interchangable in my understanding). Currently I am working on a mapping software which allows to visualize ...
2
votes
1answer
98 views

How to make slope map from elevation map in Lat/Long?

I have an elevation raster map of the world, in Lat/Long. When I make a slope map, the results of the raster cells will be either 0, or values close to 90. The problem seems to be that the Slope ...
2
votes
1answer
69 views

Natural Earth doesn't render well in Robinson World projection

QGIS Pisa 2.10.1 Mac Pro, Mac OS I don't seem to be able to create a simple World Map using the Natural Earth Dataset and the Robinson World projection, unless I zoom in. What could be the problem? ...
1
vote
0answers
32 views

Data not showing in QGIS when connecting to Oracle

I have an Oracle XE 11g spatial database that is connected to a web map. All the layers of the web map are stored in the database and they work just fine. I sometime need to edit some of the layers in ...
2
votes
3answers
149 views

What is the altitude difference between WGS84 and NAD27 Zone II?

I have a point cloud in a piece of software and have exported the point in both WGS84 and NAD27 State Plane California Zone II (in US survey feet). The WGS data looks like this, with elevation in ...
0
votes
0answers
41 views

Does Leaflet handle TopoJson in OSGB EPSG:27700 projection?

I already have a Leaflet map showing custom base map tiles in British OSGB projection, EPSG:27700 (using the Proj4Leaflet plugin). I would like to overlay some nationwide admin boundary data in the ...
2
votes
3answers
143 views

How to create a Projection from a CRS string using pyproj?

I'm trying to convert between two coordinate systems using pyproj: import pyproj p1 = pyproj.Proj("+init=EPSG:4326") p2 = pyproj.Proj("""PROJCS["NAD27 / California zone ...
0
votes
0answers
31 views

Old MIller projections Bipolar Oblique Conic Conformal/Oblated Stereographic definitions?

I'm attempting to georeference and warp some old toposheets that are various old projections including the following: Miller Oblated Stereographic Projection Bipolar Oblique Conic Conformal What's ...
4
votes
3answers
4k views

How to convert a NetCDF file to GeoTIFF using GDAL

I have a NetCDF file which contains data for the number of rain days in the UK. I'd like to convert it to a GeoTIFF, but can't get GDAL correctly georeference it. See dumps from gdalinfo below. I ...
1
vote
0answers
33 views

GPS point elevation vs Contours layer elevation

I have some survey grade GPS points whose elevation is approx 55 feet lower than my contours layer elevations. I am using 1 ft contours and comparing point elevations with contours in the same ...
1
vote
1answer
102 views

Using OSGB (ESPG: 27700) projection in Openlayers with MousePosistion

I am trying to display Ordnance Survey Grid references (ESPG:27700) on a set of BaseMaps with the MousePosistion control. From looking through the OpenLayers samples and this forum samples I have ...
0
votes
0answers
26 views

Project (Data manager) plus Add XY results in new data being rotated

I have point data in decimal degrees. When I want to convert to local UTM data I have going through the usual Project (Data Manager) to project from LAT/Long to UTM and then when I add XY to the new ...
0
votes
1answer
33 views

Batch reproject shapefiles in subdirectories

I have a catalog tree and in every folder I have a number of shapefiles, images and mxd files. The shapefiles are all in Greek Grid projection system (EPSG: 2100). What I want to do is to batch ...
1
vote
2answers
128 views

Why does the OpenLayers plugin override the predefined projection?

What I am trying to say is: You import a shapfile into an empty QGIS and the QGIS environment gets the projection system of the imported shapefile. You import another shapefile into QGIS. The ...
2
votes
3answers
889 views

Can I use Openlayers Plugin with a different Datum/Projection?

There is probably already a post for my problem, but after long searching, I could not find a solution for my issue. I am working with QGIS und I am using the following projection/datum: MGI / ...
0
votes
1answer
30 views

Reproject OpenLayers.Layer.OSM

In my map a set projection and displayProjection as EPSG:3763 and i can see my vector layers...they are EPSG:3763 Projections. Now i need a simple map behind my vector layers and i put this layer: ...
0
votes
0answers
32 views

How to get a mercator projection from a “disk photo”

I'd like to build a real 3d globe of Pluto using latest images made available from New Horizons. I know how to convert a mercator projection into a "12-gores" projection, suitable to be glued over a ...
0
votes
4answers
1k views

Distort image to Mercator Projection view

i have an image that rendered from data i have on my DB. i need to convert this image, with Mercator Projection method, to distorted image that when i'll wrap a 3d sphere with it it'll looks ...
0
votes
1answer
63 views

Are ArcGIS' UTM zone designations simplified?

I was recently given a document showing the UTM zones as they appear over the whole Earth. Each zone is 6 degrees longitude by 8 degrees latitude. A numbering system proceeds from 1 to 60 from -180 ...
0
votes
1answer
52 views

What is the type of EPSG of longitude/latitude (not Point) co-ordinates?

I want to know that what is the type of projection (900913, 4326 or so on..) of long/lat co-ordinates. I happen to come across a slight confusion while querying planet_osm_lines when I dump ...
1
vote
1answer
965 views

help with TMS (gdal2tiles) Openlayers 3 and custom projection

I work with a local italian projection (EPSG:3003 Monte Mario Italy zone 1) and I had loaded this projection in my project for evitate to reproject all of my data. I had created the tile pyramid with ...
2
votes
1answer
344 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 ...
0
votes
1answer
79 views

Shapefile extent units in decimal degrees but values in meters

I have a shapefile that had its geographic coordinate system defined as the projection NAD 83 UTM Zone 18. The scale of the layer was correct but it was at the wrong point in space. I redefined the ...
3
votes
3answers
89 views

How to overlay a map of Europe on a map of Australia?

I'd like to overlay the cities of Europe on Australia for distance/size comparison purposes using QGIS and I'm wondering how best to achieve this while preserving distance between the European cities? ...
2
votes
1answer
216 views

Create Circle and Marker on Click in OpenLayers

I want to create a marker and buffer around it with a given radius on map click event. Marker is displayed successfully but the polygon doesn't display. I guess there is problem in projection setting. ...
0
votes
0answers
37 views

Setting units for arcpy fishnet tool, given unprojected input

I'm trying to use arcpy to create a grid over each of a large number of metropolitan areas across the US. I'm iterating over each metro and trying to create a grid over each one using the "fishnet" ...
0
votes
1answer
48 views

Getting wrong values trying to convert to a latitude longitude system

By using listgeo I got the following information: PCS = 31468 (name unknown) If I am not mistaken this translates to DHDN / 3-degree Gauss-Kruger zone 4, and by using this site I got a proj4 ...
1
vote
1answer
36 views

Choosing projection for calculating 2D 3D area in New Zealand?

I'm trying to use Surface Volume tool in ArcMap to calculate 2D and 3D area of a catchment. What would be the best projection to use and how do i check the maximum error of the estimation?
2
votes
1answer
222 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 ...
3
votes
1answer
90 views

Tilted projection in QGIS

I'm trying to add tpers projection as a custom projection in QGIS 2.10.1 In the Custom crs dialog I'm adding the proj.4 text: +proj=tpers +h=500000000 +lat_0=19 +lon_0=99 +x_0=0 +y_0=0 +a=6371000 ...
0
votes
0answers
28 views

Projection Discrepancy

I'm creating a system that pulls Longitude/Latitude data from the MapQuest hosted Nominatim service. I'm using OpenStreetMap/OpenLayers to display markers on a map. In order to compute the location to ...
2
votes
1answer
166 views

Trying to set NAD 1983 EPSG 102631 in QGIS

I was able to find the right coordinate system online NAD 1983 Alaska But now I don't know what to do. I can't find the coordinate system on QGIS. When I choose the one I think is correct it warps ...
5
votes
1answer
176 views

Projecting a world map on 6 segments to print on ball

Working with QGis and data from Natural Earth I would like to prepare a world map (1:50 000) for a globe that can be printed in 6 segments, which glued together build a ‘sphere’ (ball) according to ...
3
votes
1answer
96 views

What projection to use to get a game map into QGIS?

I have built and maintain a SWTOR game map atlas. At the moment, it's all static jpg maps, but I would like to get the info into an actual GIS software to get more functionality and make my website ...
0
votes
0answers
36 views

reproject satellite orbit values from irregular grid to regular grid

I have a ncdf file containing measurements covering a satellite orbit. The ncdf contains the corresponding latitude / longitude fields but they ar irregularly spaced. I tried rasterizing the values ...
0
votes
0answers
28 views

QGIS to Leaflet Projection Weirdness

I've been using the mmqgis tool to create a hex grid. It loads up in QGIS looking good, but when I save it as geojson and load it up in leaflet it gets stretched (see attached). It starts life as ...
0
votes
1answer
37 views

ArcGIS: Goode Homolosine Projection and Inconsistent Extents

I recently posted about a problem in ArcGIS using the Goode Homolosine (Land) projection with the Project Raster tool HERE. The problem was related to a bug with that tool, and a workaround solution ...
1
vote
1answer
86 views

Copy GeoTIFF metadata to TIFF using ArcPy

I have conducted some image manipulation on GeoTIFFs in a program and the resulting TIFFs now have no spatial information attached. Their x,y origins are (0,0). Since these processed images are of ...