Re: Incorrect re-projection from EPSG:4326 to 3857

"Zhiyu (Drew) Li" <[email protected]>
Newsgroups gmane.comp.gis.grass.user
Message-ID <CAMmsbUn4a0fcQ6gi9qVqeew3+nRFsBgHJNQxuGPvtVtrEyz-=w@mail.gmail.com>
Hi there,

I just tried the same 4326 to 3857 re-projection with dockerized 7.5 trunk.
The results are correct.

Thanks so much!
Drew

On Thu, Jan 4, 2018 at 10:38 AM, Markus Neteler <[email protected]> wrote:

> On Thu, Jan 4, 2018 at 6:25 PM, Markus Metz
> <[email protected]> wrote:
> > On Thu, Jan 4, 2018 at 9:08 AM, Helmut Kudrnovsky <[email protected]> wrote:
> >>
> >> Zhiyu (Drew) Li wrote
> >> > Hi there,
> >> >
> >> > I was trying to re-project a EPSG:4326 coordinate into EPSG:3857 using
> >> > GRASS, but I found GDAL gave me a different result.
> >> >
> >> > GRASS (7.2.2):
> ...
> > Regarding EPSG:3857:
> > Uses spherical development of ellipsoidal coordinates. Relative to WGS
> 84 /
> > World Mercator (CRS code 3395) errors of 0.7 percent in scale and
> > differences in northing of up to 43km in the map (equivalent to 21km on
> the
> > ground) may arise.
> >
> > This has been fixed in recent GRASS 7.4 and GRASS 7.5, providing same
> > results like GDAL.
>
> I have added a related note here for the upcoming 7.4.0 release:
>
> https://trac.osgeo.org/grass/wiki/Release/7.4.0-News#Projectionsupport
>
> markusN
> _______________________________________________
> grass-user mailing list
> [email protected]
> https://lists.osgeo.org/mailman/listinfo/grass-user
>

_______________________________________________
grass-user mailing list
[email protected]
https://lists.osgeo.org/mailman/listinfo/grass-user
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.