Campo Inchauspe towgs84 parameters?

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|

Campo Inchauspe towgs84 parameters?

Markus Neteler-3
Dear list members,

we try to figure out the Campo Inchauspe to WGS 84 parameters to
reproject LANDSAT7 data from CONAE:

gdalinfo L71229083_08320020426_HTM.FST
Driver: FAST/EOSAT FAST Format
Size is 6920, 5960
Coordinate System is:
PROJCS["unnamed",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563,
                AUTHORITY["EPSG","7030"]],
            TOWGS84[0,0,0,0,0,0,0],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9108"]],
        AXIS["Lat",NORTH],
        AXIS["Long",EAST],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",-66],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",500000],
    PARAMETER["false_northing",10002288.3],
    UNIT["Meter",1]]
GeoTransform =
  548152.569386061, 29.49069590981356, -5.504468031548917
  6435853.497547253, -5.504408151466975, -29.49068635677127
Metadata:
  ACQUISITION_DATE=20020426
  SATELLITE=LANDSAT7
  SENSOR=ETM+
  BIAS1=0.000000000000000
  GAIN1=0.066823529411765
  BIAS2=3.200000000000000
  GAIN2=0.037058823529412
Corner Coordinates:
Upper Left  (  548152.569, 6435853.498) ( 65d29'21.08"W, 32d13'14.35"S)
Lower Left  (  515345.940, 6260089.007) ( 65d50'3.36"W, 33d48'23.03"S)
Upper Right (  752228.185, 6397762.993) ( 63d18'55.40"W, 32d32'11.40"S)
Lower Right (  719421.556, 6221998.502) ( 63d37'17.87"W, 34d 7'36.72"S)
Center      (  633787.063, 6328926.000) ( 64d33'56.11"W, 33d10'39.39"S)
Band 1 Block=6920x1 Type=Byte, ColorInterp=Undefined
Band 2 Block=6920x1 Type=Byte, ColorInterp=Undefined

The LANDSAT7 header does not contain the towgs84 parameters.

So I was looking at the EPSG 6.4/6.8 SQL databases which do contain these
parameters:

epsg_v68: Query Results
coord_op_name   coord_op_method_name    parameter_name  sort_order      parameter_value unit_of_meas_name       area_name
Campo Inchauspe to WGS 84 (1)   Geocentric translations X-axis translation
1       -148    metre   Argentina
Campo Inchauspe to WGS 84 (1)   Geocentric translations Y-axis translation
2       136     metre   Argentina
Campo Inchauspe to WGS 84 (1)   Geocentric translations Z-axis translation
3       90      metre   Argentina

However, we found different parameters mentioned in the Grids & Datums column
"THE REPUBLIC OF ARGENTINA" (12/1999), at
http://www.asprs.org/resources/grids/12-99-argentina.pdf

It is correct to use the parameters of EPSG?
If so, would it be possible to add them to the PROJ4 EPSG file?

Thanks in advance

 Markus Neteler
_______________________________________________
Proj mailing list
[hidden email]
http://lists.maptools.org/mailman/listinfo/proj
Reply | Threaded
Open this post in threaded view
|

Re: Campo Inchauspe towgs84 parameters?

Frank Warmerdam
On 11/11/05, Markus Neteler <[hidden email]> wrote:

> So I was looking at the EPSG 6.4/6.8 SQL databases which do contain these
> parameters:
>
> epsg_v68: Query Results
> coord_op_name   coord_op_method_name    parameter_name  sort_order      parameter_value unit_of_meas_name       area_name
> Campo Inchauspe to WGS 84 (1)   Geocentric translations X-axis translation
> 1       -148    metre   Argentina
> Campo Inchauspe to WGS 84 (1)   Geocentric translations Y-axis translation
> 2       136     metre   Argentina
> Campo Inchauspe to WGS 84 (1)   Geocentric translations Z-axis translation
> 3       90      metre   Argentina
>
> However, we found different parameters mentioned in the Grids & Datums column
> "THE REPUBLIC OF ARGENTINA" (12/1999), at
> http://www.asprs.org/resources/grids/12-99-argentina.pdf
>
> It is correct to use the parameters of EPSG?
> If so, would it be possible to add them to the PROJ4 EPSG file?

Markus,

Is there really only one EPSG translation to WGS84
offered?  If so, I am surprised it isn't already in the EPSG
file.  Perhaps it was added since 6.5 that I last used.

Looking at Cliff's column, it seems EPSG shift is quite
different than the NIMA one Cliff indicates.  This would
make me quite nervous about picking just one of them as
authoritative.  I would add that "custom overrides" for
datums are very hard for me to maintain currently.

I do hope to reprocess the EPSG 6.8 database soon, and
if the autotranslation picks the -148,136,90 solution then that
will appear in the file.

Best regards,
--
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, [hidden email]
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent

_______________________________________________
Proj mailing list
[hidden email]
http://lists.maptools.org/mailman/listinfo/proj
Reply | Threaded
Open this post in threaded view
|

Re: Campo Inchauspe towgs84 parameters?

Markus Neteler-3
In reply to this post by Markus Neteler-3
Frank Warmerdam wrote:
> Markus,
>
> Is there really only one EPSG translation to WGS84
> offered?  If so, I am surprised it isn't already in the EPSG
> file.  Perhaps it was added since 6.5 that I last used.

Frank, I also found it in EPSG 6.4 and only found a single
set of (3) parameters as posted.

> Looking at Cliff's column, it seems EPSG shift is quite
> different than the NIMA one Cliff indicates.  This would
> make me quite nervous about picking just one of them as
> authoritative.

Right, hopefully we can find an answer in this forum.

> I would add that "custom overrides" for
> datums are very hard for me to maintain currently.
>
> I do hope to reprocess the EPSG 6.8 database soon, and
> if the autotranslation picks the -148,136,90 solution then that
> will appear in the file.

There must have been a reason to not having it already since it
is already in the EPSG V6.4 SQL DB. Maybe my query is wrong.

Best regards

 Markus

_______________________________________________
Proj mailing list
[hidden email]
http://lists.maptools.org/mailman/listinfo/proj