Dear Roger,
I have been following this thread for some time when questions were
raised last year about finding north-south.
Like John C, with my own house as the test object, I have used plumb
lines, slot-in-a-card methods, and large scale plans. The latter uses
our acclaimed Ordnance
Doug,
I'm in complete agreement with all the excellent points you make! A
GPS-derived bearing can't be accurate to 0.1 arcsecond -- that's absurd. I
just meant that the latitudes and longitudes of an accurate GPS fix agree with
Google Earth's coordinates (on the WGS84 datum) to roughly that
To Jim and anyone who measures wall declinations:
Ever since Roger Bailey told us about his idea for getting an approximate
wall declination measurement by using a Google satellite image, I have been
using a variation of it for measuring walls in distant locations that I
can't measure physically.
Earth's geographic grid
To Jim and anyone who measures wall declinations: Ever since Roger Bailey
told us about his idea for getting an approximate wall declination measurement
by using a Google satellite image, I have been using a variation of it for
measuring walls in distant locations that I
At 11:01 AM 1/26/2007 -0500, J. Tallman wrote:
I guess I am not entirely willing to automatically accept their output
as 100% perfect...and I wonder if anybody on the list has any
interesting thoughts or practical experience re: Google Earth and the
accuracy of their geographic grid.
Jim,
