Am 03.04.2014 21:43, schrieb Richard Z:
On Thu, Apr 03, 2014 at 06:08:46PM +0100, Dave F. wrote:
On 02/04/2014 17:14, Richard Z. wrote:
as explained in the rationale the dimensions of the bridge/culvert
are frequently only a fraction of the achievable precision. Think
of a track crossing a small creek in a forest valley int the
mountains. The GPS precision will be 10 meters if you are lucky,
the brunnel 2-3m. Mapping this the old fashioned way will produce
junk data, not precision.
Rubbish. Please don't rely on a GPSr. It is only one, of many, ways
to survey. If I see a small bridge over a stream, say 3m I'll map is
as that, because that's how it accurately is in the real world. Some
users have access to detailed aerial imagery to help map accurately.
so again: *** <<a small creek in a forest valley int the mountains >> ***
Where is your aerial imagery? I want that!!!!!!
In the mountains you are very lucky if your imagery has less than 10 meter
offset and forests render most aerial imagery useless.
The offset (either GPS or imagery) has influence on _where_ you can map
the bridge - but not much on _how_ you are able to map it.
I'm neither a friend of a "crossing" node when there is no connection in
reality.
Missing or loosing the "bridge" tag I would always assume a ford there ...
Georg
_______________________________________________
Tagging mailing list
[email protected]
https://lists.openstreetmap.org/listinfo/tagging
