[Tagging] tagging towers WAS Re: tall masts supported by guywires

[David Groom]

----- Original Message ----- 
From: "M∡rtin Koppenhoefer" <dieterdreist at gmail.com>
To: "Nathan Edgars II" <neroute2 at gmail.com>
Cc: "Tag discussion, strategy and related tools" <tagging at openstreetmap.org>
Sent: Saturday, September 11, 2010 5:08 PM
Subject: Re: [Tagging] tagging towers WAS Re: tall masts supported by 
guywires


> 2010/9/11 Nathan Edgars II <neroute2 at gmail.com>:
>> On Sat, Sep 11, 2010 at 11:39 AM, M∡rtin Koppenhoefer
>> <dieterdreist at gmail.com> wrote:
>>> 2010/9/11 Nathan Edgars II <neroute2 at gmail.com>:
>>>> It's a guyed tower.
>>>
>>> a tower is "self-supporting", which might be read as contradictory to
>>> guys (unless you consider the guys being part of the tower itself).
>>
>> Then explain the heavy use of "guyed tower" by professionals:
>> http://www.google.com/search?q=%22guyed+tower%22
>> You may be using the dictionary definition of tower (though the
>> dictionaries I checked don't rule out guy wires on a tower), but it's
>> apparently not a distinction that's always made in the real world.
>
>
> well, probably a "guyed tower" is a such (complete term) and not a
> "tower". A tower can (structurally) usually be regarded a cantilevered
> system, see this schema:
> http://upload.wikimedia.org/wikipedia/de/0/09/Eulerfaelle1.png (the
> first case on the left).
>
> I'm not really (at this point of the discussion) objecting against
> tagging those (with appropriate subtags) as man_made=tower in OSM, but
> I wanted to raise the awareness that it is structurally not correct.
> We might discuss this and come to the conclusion, that for simplicity
> reasons we might still tag these as tower.
>
> What do you think about the changes to tower:construction and
> suggested extended subtagging?
>

My personal opinion is that the man_made=tower tag is getting a bit generic, 
in that it seems to be for any man made structure which is tall.

Personally I'd like to see a different top level tag to differentiate 
between more solid structural towers such as towers
http://www.visitingdc.com/images/eiffel-tower-picture.jpg
http://www.canadaphotoseries.com/files/canada/images/Toronto-CN-Tower.jpg
http://media-cdn.tripadvisor.com/media/photo-s/00/13/f5/fa/qutab-minar-tower.jpg

and what are more commonly thought of as  "masts" (though I accept that the 
industry definition of these probably are lattice towers, or solid towers) 
such as
http://en.wikipedia.org/wiki/File:Rowridge_from_entrance_gate_200704270010.jpg
http://www.cuphosco.com/images/GSM1.gif

though I accept that there will be problems in cases such as

http://www.freefoto.com/images/04/02/04_02_58---Mobile-Phone-Mast_web.jpg?&k=Mobile+Phone+Mast

where is this a tower, or a mast, according to my definition above?

David

> cheers,
> Martin