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4

When geographic coordinates are plotted "without projection", they are really being projected via the Simple Cylindrical (aka, Equirectangular, or Plate Carrée) projection. (It goes by many different names.) Geographic coordinates, as latitudes and longitudes, are said to be unprojected because they define positions on a (curved) sphere or ellipsoid – ...


4

The first (WGS 1984 UTM 33 North) has map units of meters, while the second has decimal degrees. If you're talking about a two-dimensional display, the WGS 1984 (decimal degree) data is often displayed using a "pseudo-Plate Carrée" projection. That is, the decimal degrees are treated as if they're linear units and the features are just displayed. A standard ...


3

According to the metadata on the data's source webpage, there are latitude and longitude values for the image which means you need to georeference it (if it isn't already) using those values. For the longitude values, I would switch to a +/-180 range, rather than a 0 to 360 range. So for the upper left longitude of 332.26, I would use -27.74 instead. ...


3

Yes. Double-click the dataframe name in the Table of Contents, or right-click it and choose Properties. On the Coordinate System tab, at the bottom, click the Transformations button. This will bring up the same dialog as when you add the layers. Here you can select the CRS of the layers present in the top box, the CRS you want to specify them to (your ...


3

EPSG:9806 is the transformation method called Cassini-Soldner, but this is not the kind of EPSG code that includes the transformation parameters which are necessary for QGIS. Usually, shapefile datasets include a .prj file with the CRS information. If you do not have it, you might go back to the place where you got the data from and look for further ...


2

You can use the Proj4 converter: http://trac.osgeo.org/proj/ Yes, it is a converter but you can convert bulk coordinates. Create a simple text file (let's say sweref99.txt) with the coordinates, e.g. 606905.22 6970515.93 635765.54 7223101.41 In order to convert all coordinates from this file the command is like this: cs2cs +init=epsg:3006 +no_defs +to ...


2

International 1924 is an ellipsoid (spheroid, in ArcGIS), not a true geodetic datum nor geographic coordinate reference system. EPSG has defined many geographic coordinate reference systems that are based on an ellipsoid, rather than on a true datum. This was done for data where the datum is not known but the ellipsoid is. If you know that a dataset is ...


2

As AndreJ assumed, I'm believe you meant EPSG::32632, WGS 1984 / UTM Zone 32 North. It's a projected coordinate reference system and its unit of measure is the meter, not decimal degrees. If your lat/lon coordinates fall within that zone, the values should range between: Easting: 200 km to 800 km Northing: 0 km to 10000 km


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Because the Earth is not a sphere, measuring the latitude from the equator plane is the only way to have circular parallels. Therefore I think that any geographic coordinate system that would not use the equator plane as a reference would have more disadvantages than advantages. If you need a specific coordinate system, I would therefore rather suggest ...


2

The coordinate system might be EPSG:2412 Beijing 1954 / 3-degree Gauss-Kruger zone 36 with the Proj.4 definition +proj=tmerc +lat_0=0 +lon_0=108 +k=1 +x_0=36500000 +y_0=0 +ellps=krass +towgs84=15.8,-154.4,-82.3,0,0,0,0 +units=m +no_defs You can use that in GDAL ogr2ogr or cs2cs, or within the QGIS GUI to display the data, and convert to any other CRS. ...


2

It seems the first dataset (vista_nicosia_links.shp) is using a different projection, most likely UTM (the zone depending on your data's location - for Nicosia, it is most likely UTM Zone 36 North). To match the coordinates properly, you have to correctly determine and define the shapefile's coordinate system (using Define Projection or changing the ...


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So I got it to work finally. The image was read only so I couldn't define spatial reference. Having fixed that the only work to be done with the available image was to define its coordinates and projection. So had to create a custom coordinate system with GCS Moon 2000 and Mercator projection (sphere). And voila no need for tedious georeference or Project ...


2

See my solution for QGIS: Export your projects to shape, and load them to qgis. If you want to use meter for your buffer distances, you have to transform your layer to meter coordinate system. The Best would be the local (country-national) coordinate systems. So save as your layers again to shape but in the CRS section choose selected CRS and load your new ...


2

Unless you really need ~millimeter accuracy you do not need a custom local system. Just use the appropriate UTM zone. UTM is metric and projected, so you will get proper distances. You can find some examples for calculating the distortion from going away from the central meridian of an UTM zone. You can keep your source data as WGS84 but be aware that at ...


1

I guess your data have lat/long coordinates ("Geographic coordinate systems" in ArcGis), so that coordinates are stored in degrees (e.g. decimal degrees). For this kind of analysis I think the use of a "Projected coordinate systems" is recommended. You can refer to the following image (Wikipedia) to find the UTM zone where your project data belongs: ...


1

It turns out the Centroid(X) and Centroid(Y) in MapInfo are not the line centre point coordinates in BNG. (However to get around the rounding problem I exported the table as a DBF). Instead, I generated these in ArcGIS instead and got perfect results. I achieved my desired result by calculating differences in X and Y values between subsections and taking the ...



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