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The choice of the reference lat/long does not create a simple shift. This shift in the XY coordinate system can be done using false easting and northing. The reference meridian is the center of the developed plane. It will be the only meridian that is parallel to the Y axis. So if you change the meridian of reference, you will shift and rotate your ...


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I think you have it "spot on" so to speak. Fundamental to the geometry of any projection is the standard line or lines -- where the "paper" touches or cuts the globe before being "rolled flat" and where there is no linear distortion. Then the practical issue is where to center the map, if it's not at 0, 0 (off the Gulf of Guinea): The center of your region ...


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ARCGIS shapefiles don't contain EPSG codes, only WKT definitions, so QGIS has to make a guess which one from its own EPSG database fits. In your case, it does not succeed, maybe due to rounding errors for x_0 and y_0. In WKT, they are in feet (like the coordinates), while the proj4 string always uses metres. You can open the .prj file from ARCGIS and ...


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I suggest that you replace the .prj of your shapefile (same name as the other files ) with the prj from Spatial Reference site, which seems to be correct. The difference in X and Y northing comes from the conversion in feet. Probably this is a rounding problem for the two WKT. PROJCS["NAD83 / California zone 3 ...


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What I did to solve this problem was: I used the pyproj library to convert from WGS84 to Robinson as here: import pyproj crs_from = pyproj.Proj(init='EPSG:4326') crs_to = pyproj.Proj('+proj=robin +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs') x, y = pyproj.transform(crs_from, crs_to, LONGITUDE HERE, LATITUDE HERE) Then I realized ...


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The value stored in a cell from a heatmap is often normalized by its area. In this case I would rather suggest an equal area projection so that you can easily aggregate to larger scale


3

According to your edit, you want to create a map (layers, featured services etc) using ArcGis for Desktop, which in turn will be used via the Javascript API in my application This is simply not possible. When you publish a map as MapService, it takes on the projection of the Map. In ArcGIS for Desktop, there is no out of the box way to change the ...


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If the Proj4 string that is stored into the GeoTIFF tags is correct this should be an easy case. Without cropping it would look like ogr2ogr -f "ESRI Shapefile" -s_srs epsg:4326 -t_srs "+proj=lcc +lat_1=47.5 +lat_0=47.5 +lon_0=4 +k_0=1 +x_0=0 +y_0=0 +a=6370000 +b=6370000 +units=m +no_defs" projected_out.shp natural_earth_in.shp For cropping to the ...


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You can use QGIS for georeferencing (tutorial), then generate tiles with it (another tutorial). Finally, you should specify layer bounds in Leaflet tile layer with bounds option.


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I'm not sure if Geotif format stores the EPSG code, or the whole projection definition in WKT or proj. If you compare the wo definitions: D:\Karten\gdal\gdal-1-11>gdalsrsinfo EPSG:32623 PROJ.4 : '+proj=utm +zone=23 +datum=WGS84 +units=m +no_defs ' OGC WKT : PROJCS["WGS 84 / UTM zone 23N", GEOGCS["WGS 84", DATUM["WGS_1984", ...


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Standard OSM tiles are in Spherical Mercator (SRID=3857) so it will probably be easiest to build your grid using the same projection. If you use SM, you might store the data at the highest zoom level OSM supports, or at the highest level zoom level you'll permit users to zoom into. If coverage is sparse, use a data structure along the lines of XIndex, ...


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The first sentence you wrote perhaps is wrong that the lat long taken from Google maps are not in WGS84 rather they are in NAD27. That is why you dont see any difference.


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You first need to decide what distortion properties would you like to control for. That is to say, are you interested in preserving area, distance or shape? There is a decision support tool for selecting projections that is quite user friendly and available for free from Oregon State University (Map Projection Selection Tool). Note that you can select the ...


3

I would recommend a Map Projection Selection tool. There is a handy selection tool from Oregon State University (Map Projection Selection Tool). With this tool you can specify which distortion property is important for your map and select the specific area of interest.


1

You can use some projections that are provided by ESRI, depending on whether distance or area is important for you. They look very similar: ESRI:102032 South_America_Equidistant_Conic +proj=eqdc +lat_0=-32 +lon_0=-60 +lat_1=-5 +lat_2=-42 +x_0=0 +y_0=0 +ellps=aust_SA +units=m +no_defs ESRI:102033 South_America_Albers_Equal_Area_Conic +proj=aea ...


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On the page that you linked to, there is a note on the bottom: DATUM: SAD-69/original PROJEÇÃO CARTOGRÁFICA: UTM-22 (-51º) OBS.: Devido ao uso do DATUM SAD-69/original por Curitiba, para converter para SIRGAS-2000, devem-se utilizar os parâmetros locais de transformação de coordenadas descritos abaixo: SAD-69/original(Curitiba) -> ...


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I finally did it by hand. The hardest part was finding non outdated informations about OSM and the library ecosystem.


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follow the instructions I gave here How to reproject a vector layer in QGIS? and you are done: before: and after:


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I tried this out and had no issues... once the data was re-projected and added to the map, I re-set the map to EPSG:3857, added the Google map via OpenLayers, and the re-projected (and projected on the fly) dataset of yours worked just fine:


3

The map object will take on the projection of the first layer you add to it, in the case of your code, the streets basemap is 102100 (web mercator). You have two options to solve this: Use your own basemap service that is in your 102726 projection so that the points from the web service show up in the correct place. Stick with arcgis online basemaps, ...


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You can do this using cartopy. #!/usr/bin/env python import cartopy import cartopy.crs as ccrs import matplotlib.pyplot as plt from pylab import imread im = imread('Robinson-projection.jpg') ax = plt.axes(projection=ccrs.Robinson()) plt.imshow(im, origin='upper', extent=[-17005833.330525, 17005833.330525, -8622512.772008, 8622512.772008], ...


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Ok finally I found the solution with postGIS st_translate select id, st_translate(geom, -0.00045, -0.00073) from tmp_che_adm3 The most important part is to find the correct offset in degrees. I think, for simply move geometries in XY is faster than qgsaffine


2

Since all the other countries seem to match, the problem seems to be with the swisserland data. Check again if u have set the right coordinate system for the layer. If it checks out, its probably a faulty dataset. If u know the offset, you could try to reproject the layer with the qgsaffine plugin. Martin Update on how to use it: -Install the plugin, you ...


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It depends on the type of analysis you are planning and how irregular your cells are. Anytime pixels are forced to become square, some amount of resampling and deformation is going to take place. You would need to provide more information about the satellite sensor your data originated from and what you're going to be doing with it in ArcGIS before I could ...


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In QGIS 2.4 (not sure about previous versions), when you right-click on the layer and choose "Save As...". On the "Save vector layer as..." dialog, be sure to change the CRS dropdown from "Layer CRS" to "Selected CRS" and then browse to "WGS 84 / Pseudo Mercator (EPSG: 3857)". Everything else should work the same and give you the output you expect.


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It's a two-stage solution: project geo-coords (lat, lon) to a Robinson map (N, E) transform the map (N, E) to a screen window (row, col) For stage 1, projection, you can use the ogr2ogr tool. Gothos explains how to use it for Robinson in particular transform-projections-with-gdal-ogr The EPSG library is extensive, but doesn’t contain everything, ...


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I wrote an in-depth article on this on my blog here: http://www.sharpgis.net/post/2007/05/05/Spatial-references2c-coordinate-systems2c-projections2c-datums2c-ellipsoids-e28093-confusing It covers all these concepts in a hopefully easy to understand manner, and has been peer-reviewed by several. To sum it up: A datum is a definition of the size, ...


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I posted an answer here which may help anyone who is having trouble importing/projecting CSV survey data: http://gis.stackexchange.com/a/109619/14731


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Use XYZ coordinate system with origin at centre of the earth. Convert lat/long of the centre of the rectangle to XYZ. Then use 3D trigonometry to compute XYZ coordinates of the vertices. Finally, convert your XYZ coordinates back to lat/long. Procedure for doing the lat/long to XYZ conversion can be found here: www.ngs.noaa.gov/TOOLS/XYZ/xyz.shtml


1

Azimuthal Equidistant Projection may work well. The origin of the projection should be set to the Lat/Long of your local area. Angles and distance from the origin are preserved. Depends on how large your 'local' area is. Distortions increase the further distance you go from the origin.


2

I believe you need a minimum of 3 points to translate, scale, and rotate. The procedure and open source code for doing this is explained here: http://docs.opencv.org/doc/tutorials/imgproc/imgtrans/warp_affine/warp_affine.html I'm assuming your images are not georeferenced, so it should not matter what your map projection is since the user only has to ...


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The MTM 1 coordinate system for Newfoundland (my guess) is found in he projected coordinate systems section, national grids then Canada and select your MTM zone. You can project these data into a UTM zone 22 keeping the same NAD83 datum between the systems


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You don't have to set the coordinate system if you have the "on the fly" option enabled. If you set the EPSG manually qgis thinks that the coord are in "GDA94/MGA Zone 50" and use the layer without transformation. Always remember that projecting "on the fly" could be a bad thing.


1

Inverting the transform isn't the way to go. Try the dataset's index() method or its code: https://github.com/mapbox/rasterio/blob/master/rasterio/_io.pyx#L878.


1

I've used this online converter successfully: http://converter.mygeodata.eu/vector



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