-------- Original Message --------
Subject: RE: Google Maps/Earth as sources
Date: Tue, 7 Aug 2012 07:42:32 +0000
From: Brendan Whyte <[log in to unmask]>
To: mapsL <[log in to unmask]>



I drew the boundaries for one section of the India-Bangladesh border
used by Googleearth. They should be good to a similar scale as the
source material I used: 1:63,360 or 1:50,000.
They match pretty darn well with the satellite imagery (in terms of rice
field bunds), but beyond the section I worked on, who knows what the
source material or its scale is.
The Burma-China boundary is pretty good in places, but in others it's
been badly digitised as line segments, rather than traced from the
1:50,000 maps that accompanied the 1960 boundary treaty. The treaty's
1:5,000 maps of several complicated sections have not been used either
by Google.

Brendan Whyte
National Library of Australia

> -------- Original Message --------
> Subject: Google Maps/Earth as sources
> Date: Mon, 6 Aug 2012 12:37:48 -0400
> From: Fry, Michael <[log in to unmask]>
> To: Maps, Air Photo, GIS Forum - Map Librarianship
> <[log in to unmask]>
>
>
>
> Some of this has been discussed here before (search the archives for a
> 2008 thread entitled "Google Earth miss-matches") but I thought I'd try
> to get an update...
>
> How do you all regard Google Maps, Google Earth, Bing Maps, etc. as
> sources for accurate boundary-related data? Aside from several
> high-profile mistakes (e.g., http://goo.gl/nP6ev and
> http://goo.gl/0gKfH), how dependable do you think Google, Bing, etc. are?
>
> I understand that Google gets more than half of its boundary files from
> the State Dept's Office of the Geographer, so there certainly are places
> where boundary data comes from a highly reputable source. But it's not
> clear to me how reliable and accurate the depicted boundaries are at
> large scales. My primary concern is that users can zoom way in--to
> scales much larger than most anything they'd ever see in print--and may
> draw conclusions about the boundaries that the underlying data, if not
> also the legal documentation, don't actually support.
>
> Am I right to think that boundaries, at the very least, should be viewed
> skeptically, particularly at large scales?
>
> Thanks.
> mf
>
> --
> Michael Fry
> Senior Map Librarian
> National Geographic Society
> 1145 17th St. N.W.
> Washington, D.C. 20036
> 202.857.7098 <tel:202.857.7098>
> [log in to unmask] <mailto:[log in to unmask]>
>