<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<div class="moz-cite-prefix"><font face="Times New Roman">Hanlie,<br>
<br>
UTM only has Longitudinal bands. Their are no, and have never
been, any Latitude bands.<br>
<br>
There is distortion on the central meridian of 4cm per 100m, and
the same at the 3 degree edges on either side. At 1 1/2 degrees
from the central meridian - the scale is 1.<br>
<br>
Regards<br>
<br>
Peter<br>
<br>
</font>
<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 2014/08/25 12:05 AM, Tim Sutton wrote:<br>
</div>
<blockquote cite="mid:53FA61BD.1080605@kartoza.com" type="cite">
<pre wrap="">-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Hi Hanlie
On 13/08/2014 08:26, Hanlie Pretorius wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hi,
I've noticed that GIS packages such as QGIS and libraries such as
PROJ4 (which QGIS uses, I think) don't use the latitude bands in
the UTM grid.
Does anyone know why the full UTM grid with latitude bands is not
implemented? Does it result in any additional distortions as one
moves away from the equator?
I have Googled about this and have not been able to find the
answer.
</pre>
</blockquote>
<pre wrap="">
I guess this is an upstream question for the epsg, gdal and proj4
projects (which we rely on for most of the projection work in QGIS). I
am not aware if it results in additional distortions as you move away
from the equator or if the bands simply provide false northings for
convenience. My limited understanding is that their distortion will
increase as you extend away in the longitudinal direction but not in
the latitudinal.
Regards
Tim
</pre>
<blockquote type="cite">
<pre wrap="">
Thanks Hanlie _______________________________________________
Africa mailing list <a class="moz-txt-link-abbreviated" href="mailto:Africa@lists.osgeo.org">Africa@lists.osgeo.org</a> You can UNSUBSCRIBE at
<a class="moz-txt-link-freetext" href="http://lists.osgeo.org/mailman/listinfo/africa">http://lists.osgeo.org/mailman/listinfo/africa</a>
</pre>
</blockquote>
<pre wrap="">
- --
-
------------------------------------------------------------------------------------------
Tim Sutton
Visit <a class="moz-txt-link-freetext" href="http://kartoza.com">http://kartoza.com</a> <a class="moz-txt-link-rfc2396E" href="http://kartoza.com/"><http://kartoza.com/></a>to find out about open
source:
* Desktop GIS programming services
* Geospatial web development
* GIS Training
* Consulting Services
Skype: timlinux
-
-------------------------------------------------------------------------------------------
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iEYEARECAAYFAlP6Yb0ACgkQqk07qZdiYjfZWgCcCLIPcxPngCuiaSB5q7eB6CIQ
CB0AoLylzPAFLkPuV2v7zwwGy6WzjbNU
=iSaj
-----END PGP SIGNATURE-----
_______________________________________________
Africa mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Africa@lists.osgeo.org">Africa@lists.osgeo.org</a>
You can UNSUBSCRIBE at <a class="moz-txt-link-freetext" href="http://lists.osgeo.org/mailman/listinfo/africa">http://lists.osgeo.org/mailman/listinfo/africa</a>
</pre>
</blockquote>
<br>
</body>
</html>