|
|
| GeoCommunity Mailing List |
| |
| Mailing List Archives |
| Subject: | Re: GISList: Help! DRGs and GPS |
| Date: |
02/13/2002 07:37:17 AM |
| From: |
Diane True |
|
|
One thing that has gotten me before is that the DRG's don't all have the
same datum. The DRG has the same datum as the paper map that was
scanned. In Missouri sometimes that's NAD83 and sometimes it's NAD27.
Another thing to remember is that the paper maps were not originally
designed to edge match. Consequently, they don't edge match very well.
About all I can say is "Good Luck",
dt
Muzrall, Daniel D. wrote:
>Hello all,
>
>I've run into a bit of a problem: Our office is working on a large project
>involving towns in both NH and VT. Part of our scope of work involves
>recording GPS data, and then overlaying the data on a DRG. The DRGs,
>obtained from Micropath, are in UTM27 Meters, Zone 19. So I've corrected
>the data, and exported it into the appropriate coordinate system. Most of
>the time this procedure works without a hitch, however, for certain town the
>data is offset by a fair degree (i.e. points situated within the town
>borders in reality, fall outside the town borders on the DRG.) The offset
>appears to be generally west or southwest, and the distance is approximately
>the same
>
>Also, I've noticed when clipping some of the DRGs (using Micropath's
>MapClipper software), that the "edge" of some of the clipped DRGs don't sit
>flush with the adjacent DRG, there's a gap of 0.5-1" east-west onscreen
>between the two, which leads me to believe that the two issues are related.
>
>My question is: Has anyone run into this problem before, and what did you
>do to resolve it?
>
>
>Thanks in advance,
>
>Dan
>
>------------------------------------------------------
>Daniel D. Muzrall
>Computer Officer/Environmental Scientist
>Roy F. Weston, Inc.
>Superfund Technical Assessment
>and Response Team (START)
>37 Upton Drive
>Wilmington, MA 01887
>p: 978-657-5400 x227
>f: 978-658-0700
>
>
>
>To unsubscribe, write to gislist-unsubscribe@geocomm.com
>________________________________________________________________________
>Setup a GeoCommunity Account and have access to FAST DataDownloads
>and Premium Career Posting at a discounted rate!
>https://www.geocomm.com/cgi-bin/accounts/login
>
>On-line Archives available at
>http://spatialnews.geocomm.com/community/lists/
>
>
--
C. Diane True
Missouri Resource Assessment Partnership
http://www.cerc.cr.usgs.gov/morap/
(USA voice) 573-441-2794
"Experience is that marvelous thing that enables you to
recognize a mistake when you make it again." -F. P. Jones
To unsubscribe, write to gislist-unsubscribe@geocomm.com
________________________________________________________________________
Setup a GeoCommunity Account and have access to FAST DataDownloads
and Premium Career Posting at a discounted rate!
https://www.geocomm.com/cgi-bin/accounts/login
On-line Archives available at
http://spatialnews.geocomm.com/community/lists/
|
|
Sponsored by:
For information
regarding
advertising rates
Click Here!
|
