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6

There's some information on the OGC Call for Comments page on the new specification for coordinate reference system WKT standard. The original specification was written by Esri many moons ago for OGC based on the mid-1990s version of the EPSG Geodetic Parameter Dataset's schema. It was revised and extended by other OGC specifications. Because it was a very ...


4

Since you work with data for Berlin, I do not believe that the second shapefile is DHDN_Soldner_Berlin. I assume the right coordinate system is EPSG 3045 - ETRS89/UTM zone 33 (N-E). Try to use Define Projection Tool (not Project Tool!) and overwrite the coordinate system information with is EPSG 3045 - ETRS89/UTM zone 33 (N-E) (the name my differs in ...


4

The projection that you use will distort the properties of your objects. You can select your projection to preserve the shape, the area OR the distances but not all at the same time. If you want a specific feature to be preserved, you need to select a projected coordinate system with this property (conformal for shape, equal-area for area or equidistant for ...


4

The ASTER L1B files contain several subdatasets with different resolutions. That's why you can not easily add them to QGIS. You have to run gdalinfo and gdalwarp on it to get a tif file that QGIS can import: gdalinfo AST_L1B.hdf >>info.txt gives you a long list of metadata. Look out for the subdatasets: Subdatasets: ...


3

I think your first solution, to project the Lat/Long coordinates to your preferred state plane is the right way to go. However, I'm not sure what you mean by "a Geometry Service". Do you mean you're using a 3rd-party web method to perform the coordinate transformation? If so, I would discourage that, as there's not a good reason to have such a dependency in ...


3

You are interested in density, so equal-area projection would be the most appropriate. However, your area is tricky because you have the pole + some low latitude (<40). (My first impression was to use a Lambert Azimuthal Equal area projection for North Atlantic but you are out of range). Therefore,a global projection is probably what you need. I ...


3

GPS is per definition always WGS84 EPSG:4326, so this should be ok. A most popular error ist to exchange lat and lon values, or forgetting negative signs for West and South degrees. And: Most GPS coordinates end up off the coast of Nigeria, because people have preset a projected coordinate system like EPSG:3857 for the project, not considering that the GPS ...


3

From ESRI: "WGS 1984 Web Mercator and WGS 1984 Web Mercator (Auxiliary Sphere) use a conformal projection that preserves direction and the shape of data but distorts distance and area. Published in 1569 by Gerardus Mercator, the Mercator projection was created for use in navigation. A straight line drawn on a map in this projection provides a bearing by ...


3

Thanks to your good description I guessed that the projection that Hummingbird is using is "WGS 84 / World Mercator" which has EPSG-code EPSG:3395. More information about this projection: http://spatialreference.org/ref/epsg/3395/ http://epsg.io/3395 ...


2

Yes - in an export like you describe here the data frame's coordinate system will be ignored and all features being copied will be both input and output in the same Geographic Coordinate System of the layer's data source which in this case is a shapefile.


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These are all for the State Plane zones which are conformal (maintain shape, not area) like UTM. They should be slightly better because they're defined for a small area than a UTM zone is. Even better, but still conformal, would be the county-level Minnesota coordinate reference systems. Instead using an equal area projection like Albers and customizing ...


2

I would suggest choosing a lambert equal area projection, centered roughly in the middle of your fishing zone: +proj=laea +lat_0=60 +lon_0=0 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs which looks like this:


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EPSG:5714 is a vertical coordinate system. QGIS can only handle 2-dimensional CRS correctly, so there is no chance to get it defined as custom CRS.


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From https://developers.arcgis.com/javascript/jsapi/esri.geometry.webmercatorutils-amd.html#webmercatortogeographic: Translates the given Web Mercator coordinates to Longitude and Latitude. By default the returned longitude is normalized so that it is within -180 and +180. But your NZTM coordinates are not in webMercator units. You have to convert ...


1

The names you marked are truely free to use, because the relevant data is in the following parameters. The .prj file has to be in WKT format, as explained here: http://www.geoapi.org/3.0/javadoc/org/opengis/referencing/doc-files/WKT.html Those keywords have to be used exactly, but not the names. Every (good) software looks at the parameters, and makes its ...


1

The shapefile exists, but it does not have any content. If you create polygons, you toggle the edit mode with the pencil icon, and add new features. If you have finished, you have to click on the Save icon next to the pencil (to save the layer content), and the save icon on the left (to save the project with all its layers).


1

Yes - when you use Calculate Geometry, using the Projected Coordinate System of the data frame to project the Geographic Coordinate System coordinates of the shapefile on-the-fly, it will have the same accuracy that you would be working with by actually projecting the shapefile and taking the measurements from that.


1

basically, you should try to use the toolbox tools for projecting rasters instead of "data>export data" as much as you can, because it gives you more control on what you do (e.g. fixing the output cell size, the resampling method). Furthermore, most of the time when you reproject your raster there will be a resampling, so the new data will be degraded. It ...


1

On the fly transform: Click the CRS status button on the lower right corner of the window. Tick the "Enable 'on the fly' CRS transformation" dialogue box. Select your desired projection and click Apply. Result: Reproject layer: Right click on layer -> "Save as..." -> CRS: Selected CRS -> Then select your CRS from the list. I recommend on the fly ...


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If your raster file has proper CRS information, you can leave out the source SRS. Sometimes (especially if you have towgs84 datum shifts), it is necessary to set the source SRS different from what is stored inside the file. And some raster files (like jpg and png) do not have any SRS information, but you might now they are in degrees, so set EPSG:4326 for ...


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Extents are computed in the native projection of the data. If you want "standard lat/lon" I believe that the easiest way is to re-project your source data physically into EPSG:4326 and compute extents from the projected file.


1

I can confirm some strange results. Let's take a simple area without islands and coasts, like Va1. The measurement tool says it is 111x155km large, so 17224 km² should be ok. It is calculated to 17099 km² by the identify tool and the field calculator. Va2 is rather complicated, because the hole of Iceland has lots of vertices. With laea projection, I get ...


1

If you are using ArcGIS Desktop, I think this link will help you with calculating area values when using data in a geographic coordintate system: http://www.gislounge.com/calculating-polygon-area-in-arcmap/


1

Yes, positional error (i.e. error in the x-y coordinates of features), means that features will not necessarily line up perfectly regardless of whether they are in the same coordinate system. Each measured point will have some level of positional error which will depend on many factors including the methods by which the data are collected, e.g. using a GPS, ...


1

This was a bug in the development version of QGIS which coincidentally was fixed yesterday! See https://github.com/qgis/QGIS/commit/3af6dbc4e1fc49b4b755a542e9583573365a4bd2 . Download the next daily snapshot and you should be right.


1

In ol.proj.transform you need to specify the fromProjection before the toProjection, then it should work. A better way to set the center is to get the current view and set the center there instead of always creating a new one. function CenterMap(lat, long) { console.log("Lat: " + lat + " Long: " + long); ...


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I agree that the data is offsetted, but it is not a constant offset. I compared it with Openstreetmap boundaries from https://osm.wno-edv-service.de/boundaries/ in blue: The Vienna borders are off to the North, but the state border to the east is almost correct. So there is not much more that you can do with the data than delete it. Take the borders from ...


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You can do with arcgis project(Data Management) tool . It will convert from one coordinate system to any other. Go to arc tools and search for Project tool in Data management and give in put your vector file and give output coordinate system whatever you want based on your your requirements.


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Considering how the coordinates were originally arrived at confirms that what you are doing is correct. Look at point P1 in the figure. To determine where it is (without a GPS signal), the first step would be to identify where the up-down (vertical) direction is. Because gravity determines that, this direction must be normal to the geoid. Therefore P1 is ...



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