-------- 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