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I need to convert lat/lon to meters as the unit of measurement to do some calculations. I found this online tool to transform my data from GEO_WGS84_Lat-Lon to LAMGe (LCC). This works for me but I have to implement the calculations in Java. I found this formulas but I don't know what I have to use for λ0 (reference longitude), Φ0 (reference latitude) and Φ1, Φ2 (the standard parallels).

The online tool says that it uses 10.5 degrees east longitude and 51 degrees north latitude for the coordinate origin.

Would this be the λ0 and Φ0? And what do I have to use as Φ1 and Φ2?

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If you are trying to match the LAMGe definition from the Koordinatentransformation 4.4 online tool, you have to have all the projection parameters.

A quick look on the online tool's source website and I was able to find the metadata for the supported coordinate reference systems. Note: The link goes to the English version of the webpage.

LAMGe, EPSG::4839 ( ETRS89 / LCC Germany (N-E) )
longitude of origin: 10.5 (10° 30')
latitude of origin: 51.0 (51° 0')
standard parallel 1: 48.66666667 (48° 40')
standard parallel 2: 53.66666667 (53° 40')

Note 2: The webpage has some things wrong, like the 4326 and 4258 lines are mixed up. It's correct on the German page here.

  • Thanks for your help. I didn't see the link for the data until you mentioned it. The sad thing is that I'm not getting the same result as the online tool. I have already checked my code several times. – Thomas Jul 11 '16 at 13:27
  • How far off are the results? – mkennedy Jul 11 '16 at 13:34
  • My result is not even close.. For example 50, 11 should be 35065.43, 119.22 but my result is 0.005486615314553569, 1.865452179627969E-5 – Thomas Jul 12 '16 at 9:22
  • Multiply by 6378137, semi major axis and it'll be closer. You should look at the Snyder book that's referenced there. It might be clearer, and has ellipsoidal equations which I'm not sure that Wolfram has. – mkennedy Jul 12 '16 at 9:58
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The origin with coordinates λ0 and Φ0 (longitude and latitude) should be roughly in the center of your study area. West of Greenwich has negative longitudes.

The parallels Φ1 and Φ2 should be taken so that your study area is mainly between them, because the distortion increases outside of them.

If your study area is stretched mainly North-South, a transverse Mercator projection could give better results than LCC.

  • My study area will be Germany. So the reference longitude and latitude should be fine. The parallels Φ1 and Φ2 should then be 6 and 15? – Thomas Jul 7 '16 at 12:11
  • No, the parallels are latitudes, not longitudes. So 48 and 54 would be fine. – AndreJ Jul 7 '16 at 15:59

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