-------- Original Message --------
Subject:        Allen SD Map Artifact
Date:   Sat, 06 Oct 2007 08:23:08 -0600
From:   Mike Flannigan <[log in to unmask]>
To:     Maps, Air Photo & Geospatial Systems Forum <[log in to unmask]>




The 1981 "Allen" South Dakota 1:50,000 scale topo has
an interesting artifact, or stretch-compress error on it
just SE of Allen, SD.  The error is located near
431537N1014945W.  I see that it is corrected on
more current versions of the map.

I only mention it here to see if anybody has an explanation
as to why this error is made in rare instances.  It appears
to be a digital processing error of some kind.

If you would like to see the error I am talking about, see
this file located here:
http://home.earthlink.net/~mikeflan/allen.jpg


Mike Flannigan