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I am trying to convert from lat/long to xy in Israel Grid 05/12:

links https://epsg.io/6991 (https://epsg.io/6991.gml)

I tried this : p = pyproj.Proj("+init=ESPG:6991") using python package pyproj but it is not defined yet.

File "_proj.pyx", line 84, in _proj.Proj.__cinit__ (_proj.c:1170)
RuntimeError: no system list, errno: 2

What is the proj code or definition string to use instead (perhaps in the format like the previous network?

+proj=tmerc +lat_0=31.73439361111111 +lon_0=35.20451694444445 +k=1.0000067 +x_0=219529.584 +y_0=626907.39 +ellps=GRS80 +towgs84=-48,55,52,0,0,0,0 +units=m +no_defs ?

HDunn
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user88351
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  • epsg.io is not the official EPSG registry, if you look on https://www.epsg-registry.org I think you'll find the parameters you are looking for – nmtoken Dec 17 '16 at 16:31
  • GDAL has EPSG:6991with the same parameters as in your string, except that +towgs84 is missing. The official EPSG registry has no datum shift transformation for it either. I guess these values are only valid for the old Israel 1993 CRS. – AndreJ Dec 17 '16 at 19:29

1 Answers1

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The proj4 library has an error identifying the difference between Israel TM Grid 2039 and IG 05/12 6991. Survey if Israel made a horrendous error and updated 2039 to include the new 7 parameter Coordinate Frame transformation, instead of the previous 3 parameter Molodansky, and left 6991 without the new and correct transformation.

I've created the correct 6991 grid, using the official parameters published by Survey of Israel

+proj=tmerc +lat_0=31.7343936111111 +lon_0=35.2045169444445 +k=1.0000067 +x_0=219529.584 +y_0=626907.39 +ellps=GRS80 +towgs84=-24.002400,-17.103200,-17.844400,-0.33077,-1.852690,1.669690,5.424800 +units=m +no_defs

You can check for yourself here.

Edit 2019: I've changed the X-rotation parameter from -0.33009 to -0.33077, as is shown in the official mapping regulations, even though Esri programs still use the former, probably wrong, parameter.

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HDunn
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  • Hi thanks for this answer, can you help me with how to use the described transformation to transform a raster in ITM projection to WGS84 projection with a gdal command. thanks. – Yohai Magan Jun 23 '21 at 09:06
  • 6991 is now correctly defined in PROJ, so something like "gdal_translate -a_srs EPSG:6991" on your existing raster should work – HDunn Jun 23 '21 at 10:21