[Proj] Help w/Timbalai 1948

[OvV_HN]

Re:

[Proj] Help w/Timbalai 1948
Mikael Rittri Mikael.Rittri at carmenta.com
Fri Jul 27 15:36:18 EST 2012

I tried the predefined instance of the latest Proj version, 4.8.0, like this 
(where
the -f stuff just gives more decimals):

>proj +init=epsg:29872 -f "%.3f"

114.4   4.175

1718563.021   1515793.018

This is nearly the same as Oscar van Vlijmen's result, except for about 5 
millimeters.

...........

Reply:

There still might be an explicable, but larger difference though.
I assumed that the coordinates were on the Everest ellipsoid.
An epsg:29872 init suggests however that the original coordinates could have 
been on the wgs84 ellipsoid.
In this init a datum transformation is defined and this will be executed if 
a cs2cs is done, so I believe.
I didn't do a datum transform.
If the given lat,lon are on the WGS84 ellipsoid and a datum transform to 
Timbalai 1948 is executed first, then the RSO coordinates will be (if I've 
done everything correctly):
1717442.659, 1516072.998 sears feet.

Oscar van Vlijmen