[gdal-dev] strange grid pattern when reprojecting

[Ramiro Marco Figuera]

Hi all,

I noticed a curious gridded pattern when using gdalwarp to reproject. I 
am reprojecting some lunar south polar DEMs in stereographic projection 
to gnomonic projection. I am using the following command: gdalwarp 
-t_srs '+proj=gnom +lat_0=-90 +lon_0=0 +x_0=0 +y_0=0 +a=1737400 
+b=1737400 +units=m +no_defs ' topo_stereo.tif topo_gnom.tif

When I create a hillshaded map using gdaldem hillshade I can see a 
gridded pattern. I did a hillshaded map with the original map and the 
grid is no there. Am I making a mistake when reprojecting or is that a 
bug? I can provide images if necessary.

Cheers,

Ramiro

-- 
Ramiro Marco Figuera
Research Associate - PhD Student
Department of Physics and Earth Sciences
Jacobs University Bremen
Campus Ring 1, 28759 Bremen, Germany
Office: Research III, Room 99b
Tel: +49 (0)421 200 3226