🚀 go-pugleaf

I'd like to know how to get a digitized form of a graph that has only a
few lines shown in MacDraw format without making it huge(<100K, at
most). For the sake of discussion, let me describe it as a simple graph
of a quadratic equation with both axis shown and a simple legend
included as well, get the picture?  Lotsa white space and only a little
dark space(lines, axis, legend(text)). I would hope there's a way of
getting this done with only the dark space "selected" as the MacDraw-type
objects. Is there any way of getting this done? say by setting the
detection level(intensity?) of Thunderscan, if not a simpler way?
     
Obviously I'm not well-versed in 'scanners' lingo, therefore could you
give this 'greenhorn' a detailed-lesson-for-the-tenderfoot in this use
of Thunderscan?
     
Your prompt e-mail replies can be sent to me and I will summarize in
another follow-up article to this group. Your time and effort are
graciously acknowledged in advance(Thanks a bunch.)
     
     
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ERIC H. ROMO
<UD069225@NDSUVM1.BITNET>
CHEMISTRY DEPT. UNIV. OF NORTH DAKOTA
GRAND FORKS, N.D.