I don't think that is fair enough if you are going to be legally
pedantic about it. The basic track was derived from NPE and you have
adjusted it, by implication you have taken into account the original
work in two ways: as a validation that the GPS trace relates to this
item, and also you have got an independent verification that the GPS
trace is at least in the right ball park. To remove the "pollution" of
the sourcing, you would need to delete the path and then start anew.
The mass of problems around licensing are exactly due to the pedantry
necessary to be legally unencumbered. It is an unattainable nirvana - it
is a fair bet that there are a fair chunk of footpaths in OSM that are
effectively derived from current OS 25k maps where people may be
surveying, but have used the OS map to check that their traces are not
corrupt, or simply have the OS map by their side while they edit. The
best OSM can hope for is that there is a GPS trail that vaguely matches
map features to give plausible deniability, and that other "local
knowledge" type sourcing can be shown to be properly surveyed if someone
decided to challenge - which leaves surveyors with a burden of keeping
notes and other evidence.
Given that it is an impossible task to be clean in a volunteer project
without imposing some rule like "no edit without GPS or signature in
blood" it would then in turn make sense to be far more pragmatic with
regard to licensing of OS OpenData than seems to be the case with some
hard liners.
In terms of goals, it does not make sense for OSM simply to be the sum
of existing open source data, OSM will only be of worth if it produces a
product (or products) superior to what is available, or unique in some
way. The various national cycle maps that are evolving are an example of
where OSM is producing value that is not available elsewhere. That is
where the surveying input comes into its own.
Spenny
Graham Jones wrote on 23/07/2010 15:18:
If I collect a GPS trace of a road that is tagged as say 'source=NPE',
I will adjust the road to match the trace, and change it to
source=survey.
That means that unless you look through the history there will be no
evidence that it was once derived from another source...but, once you
have surveyed it, I don't think it is derived from the other source
any more, so this is fair enough?
Graham.
On 23 July 2010 14:42, Chris Fleming <[email protected]
<mailto:[email protected]>> wrote:
On 22/07/10 16:25, Richard Fairhurst wrote:
Ed Avis wrote:
As an aside, I think the 'source' tag is a bit
misconceived; it would make
much more sense to tag source on the changeset, not on
each object it
touches.
Only if you solely use one source per changeset. I'll
typically use at least
a mix of NPE, OS OpenData, GPS survey and personal knowledge,
and sometimes
more.
I tend to do the same - although if I have a track for a road that
was previously source = "not survey" I will generally modify it
to match the tracks and either delete the source tag or edit it to
be source=survey
Although I don't think I'm consistent. What do people tend to do?
One I did recently is
http://www.openstreetmap.org/browse/way/4981553/history and shows
the evolution of what is initially a traced name = FIXME into a
fully surveyed way by 4 people over nearly 3 years :)
Although this is a good case of where an area appears done and so
I didn't visit it, until the the OS comparsion stuff came out. At
which point I've discovered lots of missing stuff.
Cheers
Chris
--
e: [email protected] <mailto:[email protected]>
w: www.chrisfleming.org <http://www.chrisfleming.org>
_______________________________________________
Talk-GB mailing list
[email protected] <mailto:[email protected]>
http://lists.openstreetmap.org/listinfo/talk-gb
--
Dr. Graham Jones
Hartlepool, UK
email: [email protected] <mailto:[email protected]>
_______________________________________________
Talk-GB mailing list
[email protected]
http://lists.openstreetmap.org/listinfo/talk-gb
_______________________________________________
Talk-GB mailing list
[email protected]
http://lists.openstreetmap.org/listinfo/talk-gb
