[Proj] Setting up a proj4 specification

[Hanlie Pretorius]

Thanks for all the help.

2011/10/19, Mikael Rittri <Mikael.Rittri at carmenta.com>:
> PS again:
>
> The AFREF newsletter No.5, January 2008,
>
> http://facility.unavco.org/kb/getattachment.php?data=ODR8SkFOIDIwMDggQUZSRUYgbmV3c2xldHRlci5wZGY%3D
>
> publishes what they call a "Molodensky-Badekas 7-Parameters transformation"
> that is "between WGS 84 and Arc 1960 datum for Kenya". I think that means
> that
> the published transformation goes in the direction from WGS 84 to Arc 1960.
> So one would need to reverse the signs of all parameters for use in Proj.4.
>
> Also, I think "Molodensky-Badekas" usually means that the rotation sign
> convention is Coordinate Frame Rotation, while Proj.4 uses the opposite
> Position Vector Transformation.  If I am right, the signs of the rotation
> parameters must be reversed once more!
>
> If I am not mistaken, the Proj.4 syntax for the transformation should be
>
>    +towgs84=-148.5133,3.4865,-298.0307,-5.9464,7.1414,2.8544,4.3955
>
> Regards,
>
> Mikael Rittri
> Carmenta
> Sweden
> http://www.carmenta.com
>
>
> -----Original Message-----
> From: Mikael Rittri
> Sent: Wednesday, October 19, 2011 12:55 PM
> To: 'PROJ.4 and general Projections Discussions'
> Subject: RE: [Proj] Setting up a proj4 specification
>
> PS:
>
> Another datum shift for Arc 1960 to WGS 84 in Kenya is
>
>    +towgs84=-179.1,-44.7,-302.6
>
> which is probably more accurate. See Clifford Mugnier's column on Kenya,
>
> http://www.asprs.org/a/resources/grids/06-2003-kenya.pdf
>
> regards,
>
> Mikael Rittri
> Carmenta
>
> -----Original Message-----
> From: proj-bounces at lists.maptools.org
> [mailto:proj-bounces at lists.maptools.org] On Behalf Of Mikael Rittri
> Sent: Wednesday, October 19, 2011 11:10 AM
> To: PROJ.4 and general Projections Discussions
> Subject: Re: [Proj] Setting up a proj4 specification
>
> Hello, Hanlie.
>
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