Re: Re: Google Maps

yes, for a test find an image of a football field  (American) and set your
measurement device for yards.  Measure the field, should be 100 yards!
Now find a high school or college track. it should be 440 yards around. But
if you try to measure the curved distance you will be making a series of
straight line approximations  (remember your calculus) that approximates
the true curved distance around the track.  (I just came up with 442.6
yards)   Another test would be to zoom in and find mile markers on the side
of a highway and compare your measurements.  Another test method is to load
a USGS topo map (like from earthprobe) into google earth and measure from
section line to section line (1 mile).



On Mon, Feb 18, 2013 at 12:50 PM, greatyoga <greatyoga-/[email protected]> wrote:

> Ralph
>
> Thanks for the reply.  Now that I think of it, I think he did use Google
> Earth and not Google Maps.  Is that very accurate for distances?
>
> Thanks
> GB
>
> --- In [email protected], Ralph Oborn <Ralph.oborn@...>
> wrote:
> >
> > Google maps uses Geo-referenced imagery. It is exactly like using a paper
> > map. for measuring distances traveled. The differences probably came when
> > you "straightened" out the curves while doing your measurements.  When I
> > use a map to measure a winding trail or road it never comes out the same
> as
> > distance on the trail.
> >  Try Google earth  it has more features and is more fun.
> >
> >
> >
> > On Sun, Feb 17, 2013 at 8:12 AM, greatyoga <greatyoga@...> wrote:
> >
> > > A friend of mine and I go ice skating on many frozen surfaces.  A year
> or
> > > so ago, I went skating on a slough with another couple.  They had a
> GPS and
> > > recorded 10.1 miles from the start to the turn around point.  My friend
> > > said he used Google Maps to measure the distance and he said it was 7
> > > miles.  I asked him if that included the many curves of the slough.  He
> > > said yes.  That is a very big difference.  Is Google Maps accurate for
> > > measuring a meandering body of water on a map?
> > >
> > > Thanks
> > > GB
> > >
> > >
> > >
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