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<DIV><FONT face=Arial size=2>As a dabbler who is only using the shpcs2cs
function to convert a NAD27 Lambert Conformal Conic shapefile to NAD83
latitude/longitude, I'm unsure if I need the grid shift files in subdirectory
\nad. My example is a shapefile representing the geological formations on
a geologic map of Arizona.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>My command line is</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>shpcs2cs AZ_GEOL.shp AZ_GEOLll83.shp -v +proj=lcc
+datum=NAD27 +lon_0=-96 +lat_1=33 +lat_2=45 +lat_0=23 +x_0=5000000 +y_0=0 +to
+proj=latlong +datum=NAD83</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>and it seems to make no difference to the output
whether conus.lla is in the \bin directory or not. With the low resolution
of this particular file, it is hard to check whether the result is really NAD83
or not. Can you tell me what transformation cs2cs actually applies in this
case? (I have seen suggestions in the documentation that the program
doesn't complain if files are missing, it just skips steps that require
them.) Am I missing a step? I'm not going to be using proj often
enough to become an expert.</FONT></DIV></BODY></HTML>