Scanning maps and GRASS

Simon Cox S.Cox at
Fri Nov 10 07:00:00 EST 1995

At 1:56 PM 9/11/95, Casey Claiborne wrote:
>Should I stamp my foot
>down and say that I want 300 dpi?

Yes - because more than likely when you are digitising (or analysing)
later you will want to zoom, etc.

The person you are talking to is probably fed up with nongs who
overdo it and blow out file sizes.  For GIS applications one must
always consider the necessary precision _on_the_ground_, and what this
translates to in terms of dimensions on the paper map that you are scanning.
So, 5m on a source map at 1:50,000, is represented by 0.1mm or 1/254 of an
etc etc

Simon Cox

Dr Simon Cox                          __  \
CSIRO Exploration & Mining         ,~'  L_|\    Australian
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