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    <div class="moz-cite-prefix"><font face="Times New Roman">For years
        I have been working in GIS with a south orientated system.</font>
      I don't understand what the problem is.<br>
      <pre class="moz-signature" cols="72">Peter Newmarch
Professional Land Surveyor
4Y GeoInformatics Pty Ltd
Tel       : +27 31 5642856
Fax       : +27 31 5643074
Mobile    : +27 82 5705859
eMail     : <a class="moz-txt-link-abbreviated" href="mailto:newmarch@land-surveyors.com">newmarch@land-surveyors.com</a> </pre>
      On 2013/08/27 02:07 PM, Frank Sokolic wrote:<br>
    </div>
    <blockquote cite="mid:521C9694.3080708@worldonline.co.za"
      type="cite">Hi Aslam,
      <br>
      <br>
      What is NGI's position on GIS data? When I've obtained GIS data
      from NGI in the past it has always been supplied as
      north-oriented, and not in the south-oriented SA CRS. Was this
      because in the past there weren't any GIS packages that supported
      the south-oriented SACRS?
      <br>
      <br>
      Now that GIS programs are starting to support the SACRS (e.g. QGIS
      2.0, ArcGIS) does this mean that NGI will start distributing GIS
      data in the correct orientation?
      <br>
      <br>
      Frank.
      <br>
      <br>
      <br>
      On 27/08/2013 12:46, Aslam Parker wrote:
      <br>
      <blockquote type="cite">Hi All
        <br>
        Can we please not call it the Lo system, it is the South African
        <br>
        Coordinate Reference System. For a detailed and authoratative
        definition
        <br>
        and explanation, please download
        <br>
<a class="moz-txt-link-freetext" href="http://www.eepublishers.co.za/images/upload/positionit_2012/SA%20Coordinate%20reference%20system%20part1+2.pdf">http://www.eepublishers.co.za/images/upload/positionit_2012/SA%20Coordinate%20reference%20system%20part1+2.pdf</a>
        <br>
        Apparently ESRI has recently  implemented the south oriented
        SACRS in
        <br>
        their software.
        <br>
        <br>
        <br>
        Aslam Parker | Director: Geo-spatial Information and
        Professional Support
        <br>
        <br>
        |Chief Directorate: National Geo-spatial Information
        <a class="moz-txt-link-abbreviated" href="http://www.ngi.gov.za">www.ngi.gov.za</a>
        <br>
        <a class="moz-txt-link-rfc2396E" href="http://www.ngi.gov.za/"><http://www.ngi.gov.za/></a>|Cape Town|
        <br>
        <br>
        Tel +27 21 658 4302|Fax +27 86 211 7919| Mobile 082 331 8501|
        <br>
        <a class="moz-txt-link-abbreviated" href="mailto:aparker@ruraldevelopment.gov.za">aparker@ruraldevelopment.gov.za</a>
        <a class="moz-txt-link-rfc2396E" href="mailto:aparker@ruraldevelopment.gov.za"><mailto:aparker@ruraldevelopment.gov.za></a>__
        <br>
        <br>
        __
        <br>
        <br>
        __
        <br>
        <br>
        PPlease consider the environment before printing this email
        and/or any
        <br>
        related attachments//
        <br>
        <br>
         >>> Peter Newmarch <a class="moz-txt-link-rfc2396E" href="mailto:newmarch@land-surveyors.com"><newmarch@land-surveyors.com></a>
        8/27/2013 11:42 AM >>>
        <br>
        If one is producing maps in a country, then its common practice
        to use
        <br>
        the national mapping system of that country. So I guess NGI does
        have a
        <br>
        policy in the sense that their is a national mapping system for
        all data
        <br>
        - which is the current Lo system.
        <br>
        <br>
        Peter
        <br>
        <br>
        Peter Newmarch
        <br>
        Professional Land Surveyor
        <br>
        4Y GeoInformatics Pty Ltd
        <br>
        Tel       : +27 31 5642856
        <br>
        Fax       : +27 31 5643074
        <br>
        Mobile    : +27 82 5705859
        <br>
        eMail     :newmarch@land-surveyors.com
        <br>
        <br>
        On 2013/08/27 11:18 AM, Frank Sokolic wrote:
        <br>
        <blockquote type="cite">ArcGIS 10+ and the soon-to-be-released
          QGIS 2.0 contain the (correct)
          <br>
          south-orientated definitions of the Lo coordinate reference
          systems.
          <br>
          However, the problem with this is that there is a HUGE amount
          of
          <br>
          spatial data in SA and neighbouring countries that use a
          <br>
          "north-facing" orientation. To convert all of this to the
          <br>
          south-orientated system will have a massive impact on the GIS
          <br>
          community both in terms of money and time. Can we afford this?
          <br>
          <br>
          Does National Geo-spatial Information (NGI) have a policy on
          which CRS
          <br>
          to use for GIS? They also supply spatial data using
          "north-orientated"
          <br>
          coordinates so perhaps they have a policy somewhere that
          states:
          <br>
          - use south-orientated coordinates for survey data
          <br>
          - use north-orientated coordinates for GIS data?
          <br>
          <br>
          Frank.
          <br>
          <br>
          On 26/08/2013 22:03, Gavin Fleming wrote:
          <br>
          <blockquote type="cite">Very topical point Frank
            <br>
            <br>
            Now that EPSG and proj4 have codes and implementations for
            the
            <br>
            south-facing LO/Hartebeesthoek94 system, it's all well and
            good except
            <br>
            as you say most GIS practitioners use north-facing, which we
            should not
            <br>
            call 'LO' at all. I wish EPSG had set up the north facing
            series
            <br>
            instead.
            <br>
            <br>
            If you get coordinates from a surveyor they are likely to be
            <br>
            south-facing, otherwise not, probably because GIS has not
            been able to
            <br>
            handle south-facing till recently?
            <br>
            <br>
            In my early GIS days if we got south-facing data, we'd flip
            it to
            <br>
            north-facing manually before continuing.
            <br>
            <br>
            There's a bit of a blocker in QGIS 1.9 at the moment where,
            if you
            <br>
            define a north-facing LO CRS (which I prefer to call
            something like
            <br>
            'SouthAfricaTM19' instead of 'LO19'), it forces '+axis=wsu'
            into the
            <br>
            definition, which makes it south-facing. I've filed a bug
            report [1]
            <br>
            about this, hoping it gets fixed before 2.0 is released.
            <br>
            <br>
            I'm working in Lesotho now on parcel data which is in north
            facing TM
            <br>
            (on the Cape datum still), though survey data comes in
            south-facing. The
            <br>
            LO/Cape datum series is also in EPSG now, but also only as
            south-facing
            <br>
            :-(.
            <br>
            <br>
            [1] <a class="moz-txt-link-freetext" href="http://hub.qgis.org/issues/8487">http://hub.qgis.org/issues/8487</a>
            <br>
            <br>
            Gavin
            <br>
            <br>
            On 26/08/2013 17:08, Frank Sokolic wrote:
            <br>
            <blockquote type="cite">Dear List,
              <br>
              <br>
              As many of you know, the South African coordinate
              reference system is
              <br>
              defined as a south-orientated system, with Westings (Y)
              increasing
              <br>
              towards the south and Southings (X) increasing towards the
              West.
              <br>
              However, in a GIS context I've only ever seen SA CRSs
              (e.g. Lo19,
              <br>
              Lo31, etc) represented with x-coordinates increasing
              eastwards and
              <br>
              y-coordinates increasing northwards.
              <br>
              <br>
              So, for example, the coordinates of the entrance to Durban
              harbour are
              <br>
              represented in Hartebeesthoek94/Lo31 as
              <br>
              Y = -5641.000
              <br>
              X = +3305647.886
              <br>
              but in practice in a GIS this point is represented as
              <br>
              X = +5641.000
              <br>
              Y = -3305647.886
              <br>
              <br>
              My question is: are there any GIS practitioners in South
              Africa who
              <br>
              use the SA CRSs in the south-orientated sense?
              <br>
              <br>
              Regards, Frank.
              <br>
              <br>
              <br>
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