Pyproj projection 0.5 meter differnce from official results (IGD05/12,IG05/12) Israel Grid

Question

I'm trying to use those parameters and I receive a difference of ~0.5m

ALON and BSHM APN Points:

coords = [
  (dms2rad([31,42,28.5694]),  dms2rad([34,36,23.92196]),  55.671),
  (dms2rad([32,46,44.34472]), dms2rad([35,1,22.74061]), 225.046),
]

Transform:

def lla_to_ig05(lon, lat, alt):
    import pyproj
    lla = pyproj.Proj(proj='latlong', ellps='WGS84', datum='WGS84')
    ig05 = pyproj.Proj("+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")
    x, y, h = pyproj.transform(lla, ig05, lon, lat, alt, radians=True)
    return x, y, h
for lat, lon, alt in coords:
  print(pd.DataFrame(lla_to_ig05(lon, lat, alt))) # pd for pandas
  print("")

Output:

               0
0  162790.443392
1  624087.953905
2      55.671000

               0
0  202456.903152
1  742717.095893
2     225.046000

Real numbers:

               0
0  162789.564
1  624088.355
2      55.671000

               0
0  202456.453
1  742718.779
2     225.046000

Any hint will be very helpful!

Answer 1

Using the official EPSG codes provides the correct results (pyproj version: 2.4.0 [PROJ version: 6.2.0]):

>>> from pyproj import CRS. Transformer
>>> cc = CRS("IGD05/12")
>>> cc
<Geographic 2D CRS: EPSG:7139>
Name: IGD05/12
Axis Info [ellipsoidal]:
- Lat[north]: Geodetic latitude (degree)
- Lon[east]: Geodetic longitude (degree)
Area of Use:
- name: Israel
- bounds: (32.99, 29.45, 35.69, 33.53)
Datum: Israeli Geodetic Datum 2005(2012)
- Ellipsoid: WGS 84
- Prime Meridian: Greenwich

>>> cc2 = CRS("EPSG:6991")
>>> cc2
<Projected CRS: EPSG:6991>
Name: Israeli Grid 05/12
Axis Info [cartesian]:
- E[east]: Easting (metre)
- N[north]: Northing (metre)
Area of Use:
- name: Asia - Middle East - Israel and Palestine Territory onshore
- bounds: (34.17, 29.45, 35.69, 33.28)
Coordinate Operation:
- name: Israeli TM
- method: Transverse Mercator
Datum: IG05/12 Intermediate Datum
- Ellipsoid: GRS 1980
- Prime Meridian: Greenwich

>>> trans = Transformer.from_crs(cc, cc2, always_xy=True)
>>> trans
<Concatenated Operation Transformer: pipeline>
Description: axis order change (2D) + IGD05/12 to  IG05/12 Intermediate CRS + Israeli TM
Area of Use:
- name: Asia - Middle East - Israel and Palestine Territory onshore
- bounds: (34.17, 29.45, 35.69, 33.28)
>>> trans.transform(lon, lat, alt)
(162789.56376679792, 624088.3548852643, 55.671)