Trying to get a raster to go from NAD83 to NAD27 with gdalwarp. Can't see any way to tell how it is choosing to do it. Is this documented anywhere? Is there any way to make it verbose so I can tell if it's trying?<br>
<br>I ran it through strace and watched it open a file called gdal_datum.csv but of course can't tell what it's trying to do.<br><br>I found this post from Frank which implies it tries to be smart and figure out the transforms without my help: <a href="http://fwarmerdam.blogspot.com/2010/03/in-last-few-weeks-i-believe-i-have-made.html">http://fwarmerdam.blogspot.com/2010/03/in-last-few-weeks-i-believe-i-have-made.html</a><br>
<br>But it's not working and since I don't know how to tell what it's doing I can't intelligently ask for help. :-)<br><br>Thanks for your patience with a n00by<br><br>Brian<br><br>Command I am using:<br><br>
gdalwarp -of HFA -co COMPRESSED=YES -t_srs ESRI::NAD_1927_StatePlane_Oregon_North_FIPS_3601.prj 11s5w34f_color_ne.sid 11s5w34f_color_ne_nad27.img<br><br>Output is in the right coordinate space (it's moved from meters to feet) but has that familiar 10 or so meter shift we get around like the NAD83-NAD27 transform failed.<br>
<br>The input file SRS looks like this<br><br>Coordinate System is:<br>PROJCS["NAD_1983_HARN_StatePlane_Oregon_North_FIPS_3601",<br> GEOGCS["GCS_North_American_1983_HARN",<br> DATUM["NAD83_High_Accuracy_Regional_Network",<br>
SPHEROID["GRS_1980",6378137,298.257222101]],<br> PRIMEM["Greenwich",0],<br> UNIT["Degree",0.017453292519943295]],<br> PROJECTION["Lambert_Conformal_Conic_2SP"],<br>
PARAMETER["False_Easting",2500000],<br> PARAMETER["False_Northing",0],<br> PARAMETER["Central_Meridian",-120.5],<br> PARAMETER["Standard_Parallel_1",44.33333333333334],<br>
PARAMETER["Standard_Parallel_2",46],<br> PARAMETER["Latitude_Of_Origin",43.66666666666666],<br> UNIT["Meter",1],<br> AUTHORITY["EPSG","102326"]]<br><br><br>