[Tagging] Tagging Cycle Route Relations vs. Ways

Martin Koppenhoefer dieterdreist at gmail.com
Tue Nov 17 23:09:40 UTC 2020


Am Di., 17. Nov. 2020 um 20:04 Uhr schrieb stevea <steveaOSM at softworkers.com
>:

> I never said to NOT use source=* tags, they are correctly used on an
> individual datum if / as it might diverge from a greater set of data that
> otherwise has another source.  In short, if ALL of the data are from a
> single source, use a changeset comment to note this.  If not, source=* tags
> are appropriate.
>


I find the source tags in general problematic, most of all those "source"=*
tags which do not relate to a specific tag. It may make sense for the
creator of the object to add it, but what if someone changes something.
E.g. you add a tag, or remove a tag, or change a value. What would you do
with an existing source tag? Easy if you base your edit on the same source,
otherwise, would you have to remove it? How much do you have to change in
order to remove it? Or should you always be adding more values to the
existing source string without ever removing anything, until you reach 255
characters and then continue in a source2-tag?

>From a practical point of view, I am mostly ignoring source tags, because
they are almost never accurate. Typically someone has added them some
versions ago and nobody in between has bothered to remove or update the
tag. To know this, you will have to dive into the object history anyway.

I have been looking around (arbitrary examples I got by searching for
amenity=* and source=Bing with overpass, first hit, tried in 3 different
areas)  https://www.openstreetmap.org/way/145393264
source=Bing: which properties are from Bing, the address? The name? The
fact it is a kindergarten? Looking at the history, I can see that the tag
was already added in version 1 and that the node positions never changed.
The geometry fits reasonably well with Bing although it is far from
perfectly matching (I'd say it fits better with ESRI for instance). Likely
the Bing imagery has changed since 2012 when this was first drawn. IMHO in
this case there is no benefit from this tag.

Another arbitrary example, from another continent:
https://www.openstreetmap.org/node/2728286792
There is quite some detail information on this node, but I find it hard to
believe any of it came from Bing (imagery).

The third example is a post office:
https://www.openstreetmap.org/way/223059928
in this case it is also hardly anything from Bing, surely neither the name
nor the post office information.


Cheers
Martin
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/tagging/attachments/20201118/16d226d8/attachment.htm>


More information about the Tagging mailing list