GAMMA Questions

Dear all,

I have repeatedly ran into the following errors/warnings when using gc_map, even when using DEMs that are substantially larger than the SLC area:
ERROR: no coverage of SAR image by DEM (in latitude/northing)
or
WARNING: incomplete coverage of SAR image by DEM (in latitude/northing)

When I had the problem again today, I found that the SLC corners reported by GAMMA are different to the ones in the *.xml file provided by DLR:
Has anyone else ran into this? It would explain the problem with the "DEM not covering the area"

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SLC_corners TDX_20151111.slc.par
*** Calculate SLC/MLI image corners in geodetic latitude and longitude (deg.) ***
*** Copyright 2014, Gamma Remote Sensing, v1.6 21-Aug-2014 clw ***
latitude (deg.):      19.48956878  longitude (deg.):    -103.40866769
latitude (deg.):      19.47837542  longitude (deg.):    -103.70568599
latitude (deg.):      18.87124633  longitude (deg.):    -103.48948645
latitude (deg.):      18.79836784  longitude (deg.):    -103.78951853

center latitude (deg.):    19.17729150  center longitude (deg.):  -103.60217102
min. latitude (deg.):      18.79836784  max. latitude (deg.):       19.48956878
min. longitude (deg.):   -103.78951853  max. longitude (deg.):    -103.40866769
delta latitude (deg.):      0.69120094  delta longitude (deg.):      0.38085084

upper left corner latitude,  longitude (deg.): 19.53  -103.83
lower right corner latitude, longitude (deg.): 18.76  -103.37

###############################################################################

While the DLR xml says:

          <lat>1.97686521586169661E+01</lat>
          <lon>-1.03417068687320807E+02</lon>

          <lat>1.98168541846115076E+01</lat>
          <lon>-1.03692974830391222E+02</lon>

          <lat>1.93947957348381657E+01</lat>
          <lon>-1.03473584085917025E+02</lon>

          <lat>1.94480646503285399E+01</lat>
          <lon>-1.03777550684198957E+02</lon>