00%">
<TR>
<TD>
<PRE>
<font color="#82140F">
set image range 5 30.5
set image grayscale black 10 white 15
</font></PRE>
</TD>
</TR>
</TABLE>
<p>

is equivalent to
<p>
<TABLE SUMMARY="Example" BORDER="0" BGCOLOR="#efefef" WIDTH="100%">
<TR>
<TD>
<PRE>
<font color="#82140F">
set image range 5 30.5
open "awk 'BEGIN {\
  for(i=0;i&lt;256;i++) {\
    print(1-(i-50)/50)\
  } \
}' |"
read image grayscale
close
</font></PRE>
</TD>
</TR>
</TABLE>
<p>

because the image formula is
<BLOCKQUOTE>
Temperature = 5C + 0.1C