[OpenLayers-Users] reprojection issue

[Nicholas Efremov-Kendall]

Hi Mike,

if you could just tell me which tools to use to do that (GDAL or Shpproj)
I'd be really grateful.
best,
Nick

On Wed, Jun 10, 2009 at 1:04 PM, Michael O'Cleirigh <
michael.ocleirigh at rivulet.ca> wrote:

>  Hello,
>
> I had a similar type of problem with WMS  in OpenLayers when showing a
> layer served through Geoserver.  i.e. The features were offset incorrectly
> when reprojected onto a Google Maps base layer.
>
> My source layer is in the NAD 83 UTM Zone 17N EPSG:26917 projection. But in
> order to get it to reproject to the Google EPSG:900913 properly I needed to
> first convert the layer into standard NAD 83 degree unit projection (4269).
>
> I see that EPSG:32632 is similar to 26917 in that its unit is meter.  Can
> you try converting the layer into the appropriate WGS84 degree projection
> first and see if that helps?
>
> Regards,
>
> Mike
>
> Hi Jan,
>
> Unless I am very much mistaken, http://www.dmap.co.uk/utmworld.htm shows
> Tunisia to be squarely in UTM 32 N. I have ArcGIS and my landsatt data for
> the region all fall into UTM 32 N, which is why I believe this is in fact
> the case.
>
>
> UTM Zone 32 N is also EPSG:32632
>
> http://spatialreference.org/ref/epsg/32632/ so I still don't know what
> going on.
>
> UTM coordinates are arbitrary cartesian points, which basically could end
> up anywhere which is why the UTM zone is needed for the origin. The only
> thing I can think is that yes, there is some issue with the projection, but
> I don't know what.
>
> On Wed, Jun 10, 2009 at 12:38 PM, Jan Martin <janmartin3 at googlemail.com>wrote:
>
>> Hi Nicholas,
>>
>> your assumption regarding your source UTM Zone beeing UTM 32N is wrong.
>>
>> Your coordinates are from Tunisia. And Tunisia is UTM 32S, not UTM 32N:
>>
>> http://upload.wikimedia.org/wikipedia/commons/8/85/LA2-Africa-UTM-zones.png
>>
>> But as you can see here EPSG:32632 is the right result of a conversion
>> from UTM Zone 32S to EPSG:
>> http://spatialreference.org/ref/epsg/?search=32632&srtext=Search
>>
>> Question remains why your coordinates from Tunisia are displayed in
>> Algeria.
>>
>> I wonder if it is OK to just use EPSG:32632 as a projection for your data,
>> or if one would have to do math on the coordinates to.
>> After all your coordinates have been recorded in *WGS84, UTM 32S.*
>>
>> Jan
>>
>>  On Wed, Jun 10, 2009 at 6:08 PM, Nicholas Efremov-Kendall <
>> n.e.kendall at gmail.com> wrote:
>>
>>>
>>> Hello all,
>>>
>>> I believe this is more of a gis question, than for OpenLayers, but the
>>> problem manifests itself in openlayers and I'm having some trouble
>>> diagnosing it. Jan provided me with some very helpful assistance, which led
>>> me to the conclusion that my projection was wrong. I'm trying to display gps
>>> point originally recorded in UTM 32N. I had mistakenly believed this was
>>> EPSG 22332, but 36232 is actually what I was going for. My problem is this:
>>> I have the points overlaid on a wms server (thanks to Jan) but they're in
>>> the wrong spot. However, when I change the EPSG code, the points don't move.
>>> Does anyone have a suggestion for why they don't move? and or for how to
>>> crack this nut.
>>> best,
>>> Nick
>>>
>>>
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>>> http://openlayers.org/mailman/listinfo/users
>>>
>>>
>>
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