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If your image uses paletted colours, you have to translate it first to RGB colours: gdal_translate -expand rgb src_dataset dst_dataset If your image is not placed correctly when loading into QGIS, use gdal_translate -a_ullr to set the bounds. Since Openstreetmap uses EPSG:3857, you can directly reproject your image to that projection with gdalwarp ...


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If I understand correctly, your LAS is already classified. Why not project it first, then convert to multi-points? The Projections and Transformations toolbox offers a Raster toolset which includes the ProjectRaster tool. Or, if the problem is actually with the conversion to multi-point, make sure your input class options are defined. I'm not a LAS expert ...


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There are two principal datums used in South Africa. These include Hartebeesthoek94 and Cape. Hartebeesthoek94 Datum is the official geodetic datum for South Africa. The Cape datum is the older of the two is no longer used. This references the Clarke 1880 ellipsoid and it was developed by Sir Thomas Maclear and Sir David Gill in the later 19th - early ...


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A possible reason for the offset may be that the land mask of the MODIS data you use does not align quite well with your coastline shape file in WGS84 coordination system. Another possible reason is that some parameters need to be adjusted when you translate MODIS' sphere to WGS84's ellipsoid. Maybe you can try to convert the data to ArcGIS raster format ...


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If you are working from land survey plats, the basis of bearing, even though it is referenced to California Grid Zone 5, should have a starting, or reference line for the basis of bearing. This should be at the beginning of the description for the easement. It may start at a section corner, or some other aliquot corner, and describe the traverse to the ...


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I am not from California but in my state the declination should be listed on the plat or record of instrument, at least it usually is. If not I believe this may help, put in the area the survey was done and the date it was done and it should give you declination. NGS has alot of cool tools btw http://www.ngdc.noaa.gov/geomag-web/ The difference between ...


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Transform your center point, use the internal and external Projection as cgarillo mentioned and then also define the Projection of your vectorLayer and your map: var center_coord = new OpenLayers.LonLat(lon, lat).transform("EPSG:4326", "EPSG:3857"); map.setCenter(center_coord, zoom); ... var geojsonLayer = new OpenLayers.Layer.Vector("GeoJSON", { ...


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(answering own question, hoisted from comment to question) It seems that I may have reversed lat,lng. Based on transforming (180,0), it seems that this epsg:3857 coordinate system is centered at the equator and scales by meters at the equator, using a circumference of the earth of 40075016.68557849m. So I guess that's how to scale the result.


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Found it.. var formatRadius = function(Circle) { var radius; if (geodesicCheckbox.checked) { var center = Circle.getCenter(); var pointOnPerimeter = [center[0], center[1] + Circle.getRadius()] var sourceProj = map.getView().getProjection(); var c1 = ol.proj.transform(center, sourceProj, ...


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Sorry. Some days without inet. So: reprojection into latlong (epsg 4326) or something adequate for the region's extent (otherwise it looks like Kandinsky), mosaic, reprojection to put favorite projection here and finally do your tiling. Enjoy.


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From the GeoTools Referencing FAQ - Can I just use Referencing without the rest of GeoTools? Yes, you will need to use the metadata module, and one of the epsg modules. Along with their dependencies such as units. Then all you need to do is: CoordinateReferenceSystem sourceCRS = CRS.decode("EPSG:4326"); MathTransform transform = ...


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I was able to figure it out. I had to create a custom project and add it to geoserver. At first, I was trying to find pre-defined projection thinking they were complicated to add to the system but it was much easier than what I though. I took a previously defined user projection in geoserver and just copied and pasted parts of the projection of the layer to ...


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You will not get lucky with predefined EPSG codes, because these are not defined for all local CRS in the world. gdalsrsinfo on the WKT definition returns: +proj=lcc +lat_1=0 +lat_2=0 +lat_0=46.66964837722222 +lon_0=-91.15277777777777 +x_0=228600.4575057151 +y_0=148551.4835661671 +ellps=GRS80 +units=us-ft +no_defs So you have to create a custom CRS to ...


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It looks like the standard term for this is an "unprojected map". There's an example here: http://www.colorado.edu/geography/gcraft/notes/mapproj/gif/unproj.gif


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I think the answer rests on what information about world rivers you want to communicate to your audience. For example, if you're trying to show a difference between the longest rivers in the world, you may want to use a projection with less area distortion. If you're trying to show where significant trade/resource rivers are, locational accuracy would be a ...


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I cannot imagine that UTM is not suitable for your purposes. Are you sure you picked the correct zone for the location of your dataset? Example: http://spatialreference.org/ref/epsg/32632/ I don't know much about P.T.L. but it seems to work similarly as UTM. It is unlikely that it is included in common GIS coordinate reference system (CRS) definitions, ...


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There are some interesting irregularities here. I'll try to generalize the answer, particularly by discussing the parameters that are zeroes in this definition but might not be in another XML-based coordinate reference system (CRS) definition. A colleague pointed out that usually XML has uses angle brackets for the attribute/value pairs. The geographic ...



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