DEED-MAPPER-USERS-L ArchivesArchiver > DEED-MAPPER-USERS > 2005-11 > 1131809195
Subject: Deed Mapper Maps Projection and Datum
Date: Sat, 12 Nov 2005 10:26:35 EST
I recently purchased a custom-sized digital raster graphic (DRG) file (these
are scanned images of USGS 1:24000 quad maps) from MapMart.com covering
about four quads in Shenandoah County, Virginia. I used MapMart's default
projection (UTM) and Datum (1927) settings. I cannot get this DRG to match the
placement I made on the Deed Mapper maps and was wondering if there is a
difference between the UTM/Datum for the DRG and Deed Mapper maps.
My Deed Mapper files contains about 17 surveys that are spread along a
north-northeast line of approximately ten miles. When I use the DRG as a graphic
instead of the Deep Mapper maps I used to place the surveys, I get a slight
counterclockwise rotation of the DRG of about 1.5 degrees. I have a solid
placement of the most southwesterly survey (county border & prominent ridge
line), so the maximum rotation problem appears in the most northeasterly survey.
It is not just my surveys that do not line up, it is the roads as well (if I
place a bogus survey at a road intersection on the Deed Mapper map, that
survey does not match the same road intersection on the DRG. I have tried to
rotate the DRG graphic using Adobe Photoshop Elements; however, although I can
get it closer, it still does not match. I am guessing that I cannot get it
to match because the center of the rotation problem is not the same as the
center of the graphic.
Does anyone know the projection and datum used on the Deed Mapper maps.
Also, has anyone had similar problems and found a way to resolve them?
Thanks, Michael Cummings