[Proj] Geodetic datum for the "Netherlands East Indies Southern Zone"?

[Clifford J Mugnier]

Your assumption is likely as good as any regarding ancient datums in Indonesia.  Note that the Dutch established these “datums” primarily in support of their rubber plantations.  Way back when, … , astro datums were just that; individual astronomical observations used as starting points for small, separated triangulation chains in support of local plantations.  The same rationale applies to old French Colonies in the “dark continent” (Africa).

Calling these old systems “datums” is largely a charitable term.

The Grid systems were primarily established in WWII for indirect artillery (and naval) fire support, and were loosely connected to terrestrial systems based on ersatz datums established as cartographic imaginations referred to by academics as “Cartographic License.”

:-)

Clifford J. Mugnier, C.P., C.M.S.
Chief of Geodesy,
Center for GeoInformatics (C4G)
266 ERAD (Research)
3531 PFT  (Academic)
Dept. of Civil & Environmental Engineering
LOUISIANA STATE UNIVERSITY
Baton Rouge, LA  70803
Research  225-578-4578
Academic 225-578-8536
Cell            225-328-8975









On 3/4/16, 1:18 AM, "proj-bounces at lists.maptools.org on behalf of Mikael Rittri" <proj-bounces at lists.maptools.org on behalf of Mikael.Rittri at carmenta.com> wrote:

>Hello all,
>
>I have come across an Indonesian map. In the legend, it says 
>that the ellipsoid is Bessel and the projection is Lambert Conic
>Orthomorphic. The projection parameters agree with the "Netherlands
>East Indies Southern Zone", covering Java and the Lesser Sunda Islands,
>as described by Clifford Mugnier in his column on Indonesia (page 1160,
>left column).
>http://www.asprs.org/a/resources/grids/10-2009-indonesia.pdf
>
>The projection is not listed in the EPSG database, as far as I can see.
>
>What I am not sure of, is the geodetic datum. The graticule of the 
>map showed longitudes from Jakarta, but that doesn't help much, since
>many local geodetic datums in Indonesia use Jakarta as the prime meridian.
>
>In the EPSG database, the only geodetic datums that fit - using the
>Bessel ellipsoid and covering Java - are Batavia and Batavia (Jakarta),
>EPSG codes 6211 and 6813. And I noticed that the "Netherlands East
>Indies Equatorial Zone", also mentioned by Mugnier, is listed in 
>EPSG (code 3001), and uses the Batavia datum. 
>
>Can I conclude that the Netherlands East Indies Southern Zone also
>uses the Batavia datum, or could it use some other datum that is
>not listed by EPSG? 
>
>Regards,
>
>Mikael Rittri
>Carmenta
>Sweden
>http://www.carmenta.com
>
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