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Yes it is little difficult to create grid in meters using WGS-84 Here is workflow which works fine for me. First create a polygon shape file which contains a bounding box of raster. Now re-project this this shape file to a projected coordinate system. Selection of projected coordinate system depends on the area where you are working, if you are not sure ...


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The N or S value of Latitude is whether the location is North or South of the Equator. W or E for Longitude, is W or E of the Prime Meridian. The number that follows the letter is the Degree of Latitude or Longitude, followed by minutes and seconds of Latitude/Longitude displayed as floats. The alpha-numeric values should not be ignored as they are part of ...


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The problem is poorly documented by authoritative sources for English speakers, despite affecting millions of people on an everyday basis. I've spend the past two days trying to understand the situation and I've created a Wikipedia article about the restrictions on mapping in China and about the China GPS shift problem. Below is the part of my research that ...


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You use a UTM zone when your area of interest fits completely within it or very nearly so. A UTM zone is not appropriate when your area of interest spans several zones such as in your case. A little overlap into a neighboring zone might be ok, but the further away from the zone you pick, the more distortion there will be and the more it matters. I found this ...


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Don't choose UTM, end of story. Many large countries choose a single sensible projection for some tasks. Victoria, a small state in my country was extremely foresighted in the late 90's and chose a Lambert Conformal Conic projection suitable for state-wide usage when they were undergoing a datum shift (ADG84/66 to GDA94), rather than hobble along with ...


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I would suggest the best approach is to find out the primary projection that the national mapping or geomatics agency of the area in question usually uses and use that. I live in canada, covering a lot of UTM Zones, and when not geographic (lat/Long) the provinces generally each use a projection that is appropriate for the size and shape of their region. BC ...


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Measurement functions on geometry types do basic calculations in Cartesian space, where the output units are the same as the input distance units. This is well understood and documented (see ST_Length). WGS84 uses degrees, so ST_Length and ST_Area have outputs in degrees and degrees². However for most practical purposes, these units do not make sense. You ...


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The cordinates are referenced by WSG84, so you dont have to reproject them, but the given coordinates are not encoded in the correct Format. In Postgis points are defined as: geometry ST_Point(float x_lon, float y_lat); That means, you have to use floating-point values as lat and lon parameters. NMEA ccordinates are defined as: Latitude: ...


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I seemed to be having this problem, but then discovered that the reason was that I had a second map included as an item in the Composer but with the tick-box empty so that it did not show. The scale bar was setting itself from this invisible second map, which had a different projection. Once I removed the second map from the Composer, everything worked ...


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I have found this WPS service to do that at the 'Institut CartogrĂ fic de Catalunya'. Or, you can see all their services here (they have a REST service to convert coordinates). Hope it helps.


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I've spent a lot of time for this question, since it dealt with a peculiar phenomenon. I guess the solution found in the projection. Attached is an ESRI resource dealing with a similar issue: Measuring distances and areas when your map uses the Mercator projection. First, it should be said that OSM tiles plugin in QGIS, and other web mapping services, using ...



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