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I'm currently struggling to convert a small .asc dataset with no defined projection. The projection that has to be first applied is Lambert Azimuthal "old" projection:

In PROJ.4

+proj=laea +lat_0=48 +lon_0=9 +x_0=0 +y_0=0 +R=6378388 +units=m

or In ArcGIS

Radius of sphere of reference  6378388m
Longitude of center of projection 9 0 0 (Degrees Minutes Seconds)
Latitude of center of projection 48 0 0 (Degrees Minutes Seconds)
False Easting 0 m
False Northing 0 m

projection lambert_azimuthal
units meters
spheroid sphere

The target projection is EPSG:3035 with

PROJ.4 

+proj=laea +lat_0=52 +lon_0=10 +x_0=4321000 +y_0=3210000 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs.

or in ArcGIS

Projected Coordinate System:    ETRS_1989_LAEA
Projection: Lambert_Azimuthal_Equal_Area
False_Easting:  4321000.00000000
False_Northing: 3210000.00000000
Central_Meridian:   10.00000000
Latitude_Of_Origin: 52.00000000
Linear Unit:    Meter

Geographic Coordinate System:   GCS_ETRS_1989
Datum:  D_ETRS_1989
Prime Meridian:     Greenwich
Angular Unit:   Degree

I'm using the Warp (QGis tool), and this is what I got.

enter image description here

Output driver **`AAIGrid' not recognised or does not support
direct output file creation. The following format drivers are configured
and support direct output**:
GeoRaster: Oracle Spatial GeoRaster
VRT: Virtual Raster
GTiff: GeoTIFF
NITF: National Imagery Transmission Format
HFA: Erdas Imagine Images (.img)
ELAS: ELAS
MEM: In Memory Raster
BMP: MS Windows Device Independent Bitmap
PCIDSK: PCIDSK Database File
ILWIS: ILWIS Raster Map
SGI: SGI Image File Format 1.0
Leveller: Leveller heightfield
Terragen: Terragen heightfield
netCDF: Network Common Data Format
HDF4Image: HDF4 Dataset
ISIS2: USGS Astrogeology ISIS cube (Version 2)
ERS: ERMapper .ers Labelled
RMF: Raster Matrix Format
RST: Idrisi Raster A.1
INGR: Intergraph Raster
GSBG: Golden Software Binary Grid (.grd)
GS7BG: Golden Software 7 Binary Grid (.grd)
PNM: Portable Pixmap Format (netpbm)
ENVI: ENVI .hdr Labelled
EHdr: ESRI .hdr Labelled
PAux: PCI .aux Labelled
MFF: Vexcel MFF Raster
MFF2: Vexcel MFF2 (HKV) Raster
BT: VTP .bt (Binary Terrain) 1.3 Format
LAN: Erdas .LAN/.GIS
IDA: Image Data and Analysis
GTX: NOAA Vertical Datum .GTX
NTv2: NTv2 Datum Grid Shift
CTable2: CTable2 Datum Grid Shift
KRO: KOLOR Raw
ADRG: ARC Digitized Raster Graphics
SAGA: SAGA GIS Binary Grid (.sdat)

What I really don't know is why I cannot find or define a new projection for the .asc files and then hopefully to transform them into the ETRS_1989_LAEA. So these probably has to be done like this (?)

  1. Define the default projection for the dataset

  2. Transform the projection to the ETRS_1989_LAEA

My question mainly focuses on (1).Any idea about how it can be done in ArcMap or even in QGIS?

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4
  • ArcMap or QGIS? The input ellipsoid has a radius that's equal to the semimajor axis of International 1924 which is used for ED 1950. I would try unprojecting to lat/lon using R=6378388 first. Then redefine as ED50 and project to the other LAEA ProjCRS. But the error message says that it can't write using the raster format you chose. Does it work if you choose something else?
    – mkennedy
    Commented May 27, 2015 at 15:35
  • Addendum: Once you have data on ED50 (rather than the sphere), you would use ED50 to WGS84 (1), EPSG:1133, to transform it to WGS84. Parameter values are -87,-98,-121.
    – mkennedy
    Commented May 27, 2015 at 15:37
  • So @mkennedy you propose firstly to define the projection as the ED50, then transform into WGS84 and then reproject it in LAEA. I' don't understand the meaning of the parameters values in the addendum.
    – GeoBar
    Commented May 29, 2015 at 5:41
  • No, I first suggested unprojecting it to lat,lon on a sphere, then redefining it as ED50. The values are from a transformation from ED50 to WGS84 which you would need for a PROJ.4 +towgs84=-87,-98,-121 option.
    – mkennedy
    Commented May 29, 2015 at 14:57

1 Answer 1

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1

The warping does not work because your output format is not able to handle the warping.

Try one of the formats listed in the error message, then use gdal_translate (or the QGIS menu translate) to transform to AAIGrid.

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