[OSGeo Africa] PRR: Kathu coordinate system

[Aslam Parker]

Hi Hanlie
 

 
The Bosman Coordinate System was used in many towns in the Northern
Cape and Free State. It is not a national coordinate system. There are
many with local origins.
 
We will respond to your query and provide full background. My apologies
for not responding earlier. Please feel free to email me the diagram and
we will provide further advice.
 

Aslam Parker | Director: Geo-spatial Information and Professional
Support
|Chief Directorate: National Geo-spatial Information www.ngi.gov.za|
Cape Town|
Tel +27 21 658 4302| Fax +27 86 211 7919| Mobile 082 331 8501|
aparker at ruraldevelopment.gov.za 
>>> Frank Sokolic <sokolic at worldonline.co.za> 2014/01/31 10:26 AM >>>
Hi Hanlie,

If the survey was done in 1968 is it not possible that the units are in

Cape feet? Not sure when surveyors switched to using metres. Are you 
able to post a scanned copy of the survey diagram?

Regards, Frank.

On 31/01/2014 09:58, Walter Smit wrote:
> OK, Gavin and I must have read the numbers too quickly...we were
wrong.
>
> I have made some enquiries and apparently the mine surveyors in the
area
> know of this system, but nobody is able to give its actual details.
Waiting
> on some more replies from surveyors, who might have more details.
>
> Is it really necessary to convert the coordinates? Can you not rather
"warp"
> the diagram itself to other known boundaries? I did this pretty
successfully
> with diagrams from the 1830s using the georeferencing toolbar in
"that other
> GIS package" and shapefiles of Farm Portions from the Surveyor
General.
>
> -----Original Message-----
> From: africa-bounces at lists.osgeo.org
[mailto:africa-bounces at lists.osgeo.org]
> On Behalf Of Walter Smit
> Sent: 30 January 2014 03:00 PM
> To: 'Africa local chapter discussions'
> Subject: Re: [OSGeo Africa] Kathu coordinate system
>
> I agree with Gavin...since it is from a surveyor and from
pre-1999...
>
> -----Original Message-----
> From: africa-bounces at lists.osgeo.org
[mailto:africa-bounces at lists.osgeo.org]
> On Behalf Of Gavin Fleming
> Sent: 30 January 2014 02:18 PM
> To: africa at lists.osgeo.org
> Subject: Re: [OSGeo Africa] Kathu coordinate system
>
> Looks like it's south-oriented transverse mercator with a central
meridian
> of 23 and an offset of some nice round number > 3000000 on the SO x
axis (or
> a local reference latitude) and it would likely be on the Cape datum.
A bit
> of playing around these parameters will hopefully position it right.
>
> Does searching on the khathu system not turn up anything?
>
> On 30/01/2014 13:56, Hanlie Pretorius wrote:
>> Hi,
>>
>> I a hand-drawn survey diagram that I need to reproduce in QGIS. The
>> area is in the Northen Cape, close to the 23° E longitude.
>>
>> The diagram was done in 1968 and its coordinate system is specified
as
>> 'Kathu System'. The y coordinates are given first, are all positive
>> and they range from about 23 000 to 49 000. The x coordinates are
>> given second and they range from +31 000 to -153 000.
>>
>> Can anyone tell me what the specifications for this coordinate
system
>> would be? I.e. the information I would need to create a WKT or
proj4
>> specification for the CRS.
>>
>> Thanks
>> Hanlie
>> _______________________________________________
>> Africa mailing list
>> Africa at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/africa
>
>
> --
> regards
>
> Gavin
>
> Gavin Fleming
> http://afrispatial.co.za
> t: 0218630660
> c: 0845965680
> f: 0866164820
>

_______________________________________________
Africa mailing list
Africa at lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/africa

=== Email Disclaimer ===================================================

“The information contained in this email is confidential and may contain
proprietary information. It is meant solely for the intended recipient.
Access to this email by anyone else is unauthorised. If you are not the
intended recipient, any disclosure, copying, distribution or any action
taken or omitted in reliance on this, is prohibited and may be unlawful.
No liability or responsibility is accepted if information or data is,
for whatever reason corrupted or does not reach its intended recipient.
No warranty is given that this email is free of viruses. The views
expressed in this email are, unless otherwise stated, those of the
author not those of Department of Rural Development and Land Reform or
its management. Department of Rural Development and Land Reform reserves
the right to monitor, intercept and block email addresses to its users
or take any action in accordance with its email use policy”.

====================================================================
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/africa/attachments/20140131/158be2d4/attachment-0001.html>