I'm attempting to scrape some co-ordinates off Google maps for an
upcomming trip to Great Britain. Getting the lattitude and longitude is
no problem....but I don't see where the map datum is specified anywhere.

That could make a difference of a few hundred meters when I load them
into my GPS and start hiking across the countryside.

Anyone see that info anywhere?

-- 
Paul Hovnanian     mailto:P...@Hovnanian.com
------------------------------------------------------------------
Dyslexics have more fnu.

Paul Hovnanian P.E. wrote:
> I'm attempting to scrape some co-ordinates off Google maps for an
> upcomming trip to Great Britain. Getting the lattitude and longitude is
> no problem....but I don't see where the map datum is specified anywhere.
> 
> That could make a difference of a few hundred meters when I load them
> into my GPS and start hiking across the countryside.
> 
> Anyone see that info anywhere?

Ordinance survey want to sell you their maps. And if you are walking 
then you really should have 1"/mile or better 2.5"/mile maps with you. 
Many paths are unclear and in poor visibility it is easy to get lost.

You could also try:
http://www.ordnancesurvey.co.uk/oswebsite/leisure/
(IE 8 not supported)

Regards,
Martin Brown

Paul Hovnanian P.E. wrote:
> I'm attempting to scrape some co-ordinates off Google maps for an
> upcomming trip to Great Britain. Getting the lattitude and longitude
> is no problem....but I don't see where the map datum is specified
> anywhere.
>
> That could make a difference of a few hundred meters when I load them
> into my GPS and start hiking across the countryside.
>
> Anyone see that info anywhere?

Most likely WGS84. (just googled it, and there are several references to 
that being the case)
Why not compare with your paper street directory? (street directories in Oz 
here have a UTM grid reference you can convert). Good enough to a few 
meters.

Dave.
-- 
---------------------------------------------
Check out my Electronics Engineering Video Blog & Podcast:
http://www.alternatezone.com/eevblog/ 

David L. Jones wrote:
> Paul Hovnanian P.E. wrote:
>> I'm attempting to scrape some co-ordinates off Google maps for an
>> upcomming trip to Great Britain. Getting the lattitude and longitude
>> is no problem....but I don't see where the map datum is specified
>> anywhere.
>>
>> That could make a difference of a few hundred meters when I load them
>> into my GPS and start hiking across the countryside.
>>
>> Anyone see that info anywhere?
>
> Most likely WGS84. (just googled it, and there are several references
> to that being the case)
> Why not compare with your paper street directory? (street directories
> in Oz here have a UTM grid reference you can convert). Good enough to
> a few meters.

BTW, the best place to ask would be a UK Geocaching forum.

Dave.

-- 
---------------------------------------------
Check out my Electronics Engineering Video Blog & Podcast:
http://www.alternatezone.com/eevblog/ 

"David L. Jones" wrote:
> 
> Paul Hovnanian P.E. wrote:
> > I'm attempting to scrape some co-ordinates off Google maps for an
> > upcomming trip to Great Britain. Getting the lattitude and longitude
> > is no problem....but I don't see where the map datum is specified
> > anywhere.
> >
> > That could make a difference of a few hundred meters when I load them
> > into my GPS and start hiking across the countryside.
> >
> > Anyone see that info anywhere?
> 
> Most likely WGS84. (just googled it, and there are several references to
> that being the case)
> Why not compare with your paper street directory? (street directories in Oz
> here have a UTM grid reference you can convert). Good enough to a few
> meters.

British Ordnance Survey maps have both latitude/longitude using a
British Grid system (similar idea to UTM). I'll try to pick a point off
the maps and Google maps and see how the coordinates compare.
 
> Dave.
> --
> ---------------------------------------------
> Check out my Electronics Engineering Video Blog & Podcast:
> http://www.alternatezone.com/eevblog/

-- 
Paul Hovnanian     mailto:P...@Hovnanian.com
------------------------------------------------------------------
If God is perfect then why did He create discontinuous functions?