n the temporary files (which this option causes
to be preserved).  If you manually run the commands that
<B>ppmshadow</B> runs on these files, you can figure out where the
problem is.  In problem cases where you want to manually tweak the
image generation process along the way, you can keep the intermediate
files with the <B>-k </B> option, modify them appropriately with an
image editor, then recombine them with the steps used by the code in
<B>ppmshadow</B>.

See the <B>ppmshadow.doc</B> file in the Netpbm