[Proj] Errors between proj 4.5 and 4.6.1 with epsg:31467

[Richard Greenwood]

On Wed, Mar 11, 2009 at 4:07 AM, Stephan Holl
<stephan.holl at intevation.de> wrote:
> Dear proj-users,
>
> a customer has updated a test-server from proj 4.5.0 to 4.6.1 linked to
> a PostGIS-DB and a UMN MapServer with a WMS on top.
>
> The result of the identical WMS-request on a server working with proj
> 4.5.0 and 4.6.1 have different results in their accurancy, about a 100m
> north-shift.
>
> Did anybody came accross this problem?
>
> I tried to scan the ChangeLog of 4.6.1 but did not find any relevant
> entries which might be the cause of this change.
>
> TIA.
>
> Best
>
>        Stephan

Stephan,

>From PROJ 4.6.0 on datum shifts are only applied if datum information
for both the source and destination coordinate systems is defined.
EPSG:31467 defines a datum. I am guessing that is the coordinate
system of your source data. Do you know what coordinate system the WMS
request is asking for, and does that coordinate system have a datum
defined, or twgs84 parameters?

Regards,
Rich	

-- 
Richard Greenwood
richard.greenwood at gmail.com
www.greenwoodmap.com