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"EPSG:3488, EPSG:NAD83(NSRS2007) / California Albers" is an equal-area projection. It is based on the Albers Conic, which is defined for the northern hemisphere. Because Sweden is within its range of definition, it is equal-area in Sweden. This means that (up to floating point rounding error) it will give absolutely correct areas. Neither the Mollweide ...


3

Set lon_0 to the middle of your study area. k can be set to 0.9996 (as UTM has). lat_0, x_0 and y_0 have no effect on the quality of the projection. They are usually set to the equator and/or the inverse of the lower left point so that all coordinates are positive.


3

If you want to reproject data from one CRS to another, DO NOT simply change the CRS with Set CRS for Layer. This will NOT reproject any coordinates. So please change the CRS back to EPSG:4326 since that is the correct CRS for your lat/lon data. Instead, use Save As... to another file name and CRS. You might want to use ESRI Shapefile format, since CSV does ...


3

The length of degree in north-south is about the same so you could use 1/110574 degree/meter as a factor. However, the farther to south or north you go the bigger the error is in east-west direction. For example, take these two shapes which have a 1 degree buffer in EPSG:4326 transformed into EPSG:32630 (UTM zone 30N). First one is from 40°N and the second ...


2

Choosing CC47 as layer CRS is wrong in most situations, because that has no influence on the coordinates of the layer. So put it back to Lambert 93. When you export the layer to DXF with Rightclick on the layer , Save As ..., you can choose CC47 for that DXF, and all coordinates will be reprojected to that CRS. Note that Project -> Export to DXF is a ...


2

The comment from @mkennedy revealed you may be missing one important part of your weighted average of Cartesian coordinates: 3780321.97159 -57867.5646271 5115866.05408 Converting these ECEF coordinates back to WGS84 actually produces an ellipsoid height parameter: 53.7184377538 -0.876990985207 -2971.299770 Notice the height is negative, and is actually ...


2

I'm not sure what NOAA thinks are the right coordinates, but I have no problem loading the file into QGIS, or reprojecting it to WGS84 with gdalwarp: QGIS uses this custom projection string: +proj=lcc +lat_1=25 +lat_2=25 +lat_0=25 +lon_0=265 +x_0=0 +y_0=0 +a=6371229 +b=6371229 +units=m +no_defs You can use the same string with pyproj.Proj(). where you ...


1

Ok, I've figured it out. It is possible to apply an affine transform onto some existing CRS using FITTED_CS. Below is an example of rotation of 60 degrees counterclockwise and movement: FITTED_CS["BPAF", PARAM_MT["Affine", PARAMETER["num_row", 3], PARAMETER["num_col", 3], PARAMETER["elt_0_0", -0.5], PARAMETER["elt_0_1", ...


1

You can define a local rotated coordinate sytem as I explained here: Using customized Coordinate System for Archaeological site data Center point and rotation have to be defined in degrees. Your idea of wrapping one projection with another is not defined in PROJ.4. You can try it out, but don't expect it to work.


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I was able to get the correct output by adding the following options to my gdalwarp command: -wo sample_grid=yes, -wo sample_steps=1000, -wo source_extra=2 -wo CUTLINE_ALL_TOUCHED=true -r cubic Thank you user30184 for pointing these out!


1

@whuber's assertion that an equal-area projection "will give absolutely correct areas" comes with an asterisk, namely, assuming that the edges of the polygon are straight lines in said projection. This is often a good approximation, particularly if the edges are short; but it is rarely strictly true. If, on the other hand, the edges of your polygon are ...


1

With a dynamic map service, you can simply request it in a different coordinate system using the spatialreference parameter. Lets assume you already have a map defined in your javascript app, with a spatial reference of 4326 (web mercator), by simply adding the dynamic map service, (with a differing supported spatial reference) it will automatically ...



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