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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problem about reprojection

I am a new GIS user, I have some problem can not be solved by myself. I get a shape file generated from an Excel file. at first, my projection is WGS_1984_UTM_Zone_48N some data are inside my country ...
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1answer
177 views

How to bulk import ESRI projections into Postgis

Where can I get a file that would allow me to bulk upload all of the ESRI projections into the spatial_ref_sys table of postgis. I know that you can get insert statements on spatialreference.org; ...
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1answer
457 views

Which BC Albers should I use and is there any difference?

I was about to calculate the area of some polygons and before I did I did some research. I found that the area of the polygon will be represented in the units of the projection used. So I did some ...
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1answer
267 views

constant deviation projecting lat lon to itm(israel tranverse mercator

i use two different ways to project lat lon data taken from google earth to ITM (Israel Transverse Mercator) and export the data to arcmap same ways i try to unproject ITM data and export the data to ...
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1answer
153 views

Projection WGS 84 is slightly displaced referring to a hillshade in QGIS

I have a hillshade and a vector layer. The vector layer is slightly displaced referring the hillshade. About lat=100m and long=175m The CRS of the project is EPSG:3397 - PD/83 / Gauss-Kruger zone 4. ...
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2answers
1k views

Cartesian world sized projection WKT/EPSG code?

I am after the EPSG code or Well Known Text (WKT) of a projection that puts the centre of the earth a 0,0,0 and each point is a cartesian XYZ distance from that. My existing data is in WGS84 ...
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1answer
128 views

Should I Reproject Data Which Has Been Captured Incorrectly?

I'm working on a project for a client which is migrating data from an Oracle database to an ESRI Geodatabase. When data for this project was initially captured over 15 years ago, the coordinate ...
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73 views

export WebMap in a different projection than the WebApi

I am quite new to the Flex WebApi world. I am using the Flex WebApi and have set up map templates to print maps out to my own template as a PDF. In my template I have the Map grid set. When I eport ...
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1answer
162 views

CRS Austrian Lambert/WGS84

I am totally new to Qgis (or GIS in total): My problem is to get two layers in same CRS to do an intersection and further analysis described in the blog of underdark (Groupstat tutorial). My is the ...
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1answer
2k views

Conversion from N,E to Lat/Long And Lat/Long to N,E will always be same? [closed]

I have an excel tool for the conversion of following lat/long: Lat: 23° 11’ 24.67503’’ S Long: 118° 46’ 6.15742’’ E , which gives me following N,E: Northing: 7,434,317.43 Easting: 680,991.69 But I ...
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218 views

Proj4 inconsistent longitude after projection

All coordinates expressed in this question are (longitude, latitude), the default for proj4. London is at (-0.1460838, 51.5170986), and San Francisco is at (-122.419302, 37.775549). According to the ...
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73 views

Projection for Tracking a Vehicle

I'm looking for the best coordinate system projection to use for cartesian calculations while a vehicle is running from its starting location to about 100 miles from that spot. The offline format ...
3
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1answer
309 views

Why are two incompatible projections used together in OpenLayers? [duplicate]

While going through the examples in OpenLayers, I notice several examples with the following code: map = new OpenLayers.Map('map_element',{ ... units: 'm', projection: new ...
4
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1answer
294 views

Error in Min. Bounding Geometry results

I'm getting consistent, weird results from using Minimum Bounding Geometry to make circle polygons. I'm not sure if a datum issue, but I'm leaning more towards something wrong with Minimum Bounding ...
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3answers
387 views

How to reproject to other projections than WGS84 or Webmercator?

I have an OpenLayers map with a vector layer to add points on. I'm using Google Maps as the base layer. After the point is added, I need to store the data in my database as lat/long and x/y. Can I ...
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5answers
10k views

OpenLayers: ALL image layers are out of place on google maps v3 and OSM base layers

Summary: I have 2 different image layers that looked fine with my old mapstraction/google maps based system. Using the same coordinates as bounds in openlayers results in a shift to the north by like ...
4
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2answers
605 views

Setting coordinate systems in gvSIG: Is the workflow similar to QGIS?

I am still learning how to use coordinate systems and projections, but I hope this basic question will be easy to answer. My goal is to be able to use either QGIS or gvSIG to create a simple county ...
4
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1answer
178 views

Global projection with zero scale distortion at non-zero latitude

I am looking for a global projection with zero scale distortion at non-zero latitude. I have tried using an Oblique Mercator projection centred at a specific latitude and longitude of centre (with ...
2
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1answer
116 views

QGIS mixing up CRS

I´ve just started working with QuantumGIS for my thesis. I ordered shapefiles with the CRS: ETRS 89 UTM Zone 33N, but QGis layer properties now shows the layer has a different CRS (namely SWERE99 TM) ...
3
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1answer
235 views

how can I know which projection has this data?

I have data in an unknown projection to me. I open it in QGIS and I see that the shapes are ok, but I need to identify the projection in order to merge this data with other stuff. The points look ...
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1answer
1k views

Great-circle lines in Equirectangular projection

Just to check that I'm on the right track: Are all great-circles on the sphere and in equirectangular projection (i.e. latitude, longitude pairs) either: meridians (i.e. going pole to pole) of the ...
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1answer
400 views

How to get DXF to show up in the right spot?

I just followed the advice of this forum post in order to export the vector layers of a PDF for usage in ArcMap. The map vector layers in the PDF were spatially referenced. I was able to export the ...
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1answer
307 views

Having trouble finding out what coordinate system a map is using, and how to convert it

I'm using Small Area shapefiles in Ireland from the Central Statistics Office (CSO) website. The link to these is here http://census.cso.ie/censusasp/saps/boundaries/ED_SA%20Disclaimer1.htm (Look for ...
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0answers
570 views

VBA Convert decimal degree to Meters button

I have 2 data frames one which has WGS data in it and the other OSGB1936. I am trying to create a button where the user can input decimal degrees (WGS) and it will zoom them to that location in ...
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0answers
180 views

What is a radar projection?

Trying to overlay a radar image(radar projection) on a mercator projected map, but have no idea about what a radar projection is. So here are my quesions: What is a radar projection? What's its ...
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303 views

What is UTM Zone 0?

I am currently working with some roadway link data and it is being projected in UTM. After importing the shapefile into GRASS I can view the map and it looks correct but when I view the projection ...
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1answer
706 views

What are Bands, Dimensions, and Histograms in QGIS?

First; I can see a band as synonymous with a channel in an image editing program like GIMP, is this correct? If so then bands play the role of color mixing and masking. Are there any other ...
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3answers
3k views

Parameters for ED50 -> ETRS89/WGS84 seven-parameter transformation which are good for Denmark?

I am looking for parameters for a seven-parameter transformation (Rx, Ry, Rz, Tx, Ty, Tz, s) from ED50 UTM (zone 32U) to ETRS89 and/or WGS84. The best match I could find is here: ...
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1answer
231 views

Why are the areas covered by 2 Universal Polar Stereographic (UPS) coordinate different?

According to http://en.wikipedia.org/wiki/Universal_Polar_Stereographic_coordinate_system. the area covering Arctic is less than Antarctic. Any reasons for it? It is due to the shape of the lands?
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2answers
347 views

Mercator projection image data

I'm trying to create a map which I can place points on within my application I found some mecator jpg images but in order to accurately place points I need to convert the lat/long to pixels so that ...
2
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1answer
189 views

Determining the transformation between a satellite image and long/lat

I'm trying to overlay some data onto a satellite image of the UK. The image is a hi-resolution version of the image below (originally from dundee university): ...
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2answers
5k views

Error 000735: Input Dataset or Feature Class: Value is required

I am a true novice when it comes to ArcGIS and computer programs like this one. Am taking a class and cannot get the Project function to work under the tool box. The path I used was ArcTool box --> ...
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1answer
251 views

Projection - Some of my data are in odd position [closed]

Some of my data has this position lon: 181 / lat: 91 So when I try to draw them on the Google map: var geographic = new OpenLayers.Projection("EPSG:4326"); var mercator = new ...
3
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1answer
190 views

How to test if two GDAL datasets are in the same projection?

I'm attemping to write a funciton to test if a list of datasets are in the same projection. Naively, I thought I could test the text of WKTs, but that does not work in the following case: ...
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2answers
953 views

Why is Format of output data grayed out on Save As dialog for Rectify?

I started georeferencing and I could not save my new "rectify" file, I don't know if is because of the raster or I did something wrong. Then I find out that my control layer is not accurate, it ...
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1answer
433 views

PROJ.4 custom projection that is Transverse Mercator with Affine post-process

I am trying to define some of my local TMAF grids in PROJ.4 so I can reproject points between the local grid and MGA95 and/or WGS84. For these grids I have the MapInfo CoordSys clause which defines a ...
3
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2answers
1k views

Display two layers with OpenLayers at once

How can i display two layers with diferent projections at once? For example i have layer with EPSG:70076 and OSM layer.
3
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1answer
1k views

Export to new projection in QGIS 1.8

I would like to use QGIS to convert a CSV file from UTM to lat/long. I imported the CSV file with the "Add Delimited Text Layer" plugin. This works fine, the data looks like it is projected properly ...
3
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1answer
724 views

Area calculation: Albers Equal Area vs Pseudo Mercator

I have a question concerning area calculations in South-East Asia for West-East range that goes from India to Eastern Malaysia and a North-South range from Northern India to Indonesia (xMin,yMin ...
3
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1answer
1k views

getting the specified geographic transformation, or at least the GCS, of a data frame

First, the TLDR digest: I'm getting a bogus value from dataFrame.geographicTransformations on some machines; how do I get the correct value as shown in the properties dialog? and/or Given a spatial ...
3
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1answer
2k views

ArcGIS 10.0/10.1 - arcpy - automate projection tool with different datum or projection

I am getting stuck with a task that is slightly different from the posts I found so far on this same website. Assumption: all layers have a defined coordinate system Problem: I would like to ...
28
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2answers
23k views

What's the difference between EPSG:4326 and EPSG:900913?

I am a bit confused on EPSG:4326 and EPSG:900913. I thought that they were both same. Though as I am placing my features over GMaps, which is EPSG:4326, I need to define the srsname of the WFS layer ...
2
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1answer
348 views

Problems with NAD27 projection in QGIS

I have some data that is in NAD27, but I am having a hard time displaying it in QGIS. I think that the problem is with the CRS. I cannot seem to find the correct NAD27 option. The closest one seems ...
0
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1answer
386 views

How can I find and fix broken raster metadata using QGIS?

I have a raster (TIFF) hillshade image that I would like to use in a mapping project. However, I'm having a hard time lining it up properly in QGIS. Through a series of investigations, I have ...
6
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1answer
151 views

Is there a name for map projections that produce two disks?

I've seen lots of world maps in the shape of two disks that touch, each one a separate projection of one hemisphere onto a disk -- usually the Western Hemisphere and the Eastern Hemisphere -- so ...
0
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1answer
512 views

How do I add a Corel Draw map as .dxf file to QGIS and how do I georeference it?

I have a vector data map of Poland, which I exported from Corel Draw. I can display the map in QGIS. At first the boundaries and subdivisions are only displayed as lines, after saving the data as ...
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0answers
164 views

Converting altitude in feet to pixels on a mercator map image

I know the question might seem farfetched given that the map is 2d. But I essentially want to project items-aircraft-above the map and I would like their altitude to be vaguely 'realistic' in terms of ...
0
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1answer
1k views

Which area measurement to trust? - The same polygon in GoogleEarth v. ArcGIS [duplicate]

Possible Duplicate: What is the most accurate coordinate system for calculating areas of polygons? I'm currently involved in comparing the "official metropolitan" areas of several cities ...
1
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1answer
138 views

Python error when running SpatiaLite with OSGB(27700)

I have a project open in QGIS and am trying to import an Ordnance Survey Address Point layer into SpatiaLite. I have recently installed the Qspatialite plugin. I open SpatiaLite in the DB Manager ...
4
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2answers
490 views

How do I Capture GDAL projection and create matching output (OGR or GDAL) shape files?

Working in C++, using GDAL and OGR: Depending on what the user has supplied for image input, I need to output point (or other) shape files in the same projection as the input raster images. The ...