[OSM-talk] source=(survey, yahoo, gps...)

[Michael Collinson]

At 11:40 08/09/2009, Valent Turkovic wrote:
>Do you use source tag? Why and how, please explain? I read the wiki page
>but I don't see many people use it and I'm wondering why.

I try to put it on everything I map. It shows fellow mappers how 
accurate my contribution is. They can make a more intelligent 
decision about whether to change it according to their own sources of 
information.

source=survey

"I went there. I took pictures/made notes. The tags and geometry are 
correct. Ways were made with GPS tracks, they should be good but may 
have artifacts."

(I should really use the gps tag as well, but I am lazy)

source=yahoo_imagery
source=Yahoo

"I traced this from Yahoo imagery. Details are not easy to see so 
things like road intersections should be checked."

source=npe

(UK) "I traced this from an old map. Relative position of the feature 
should be accurate but absolute location may not be accurate. The 
feature may have changed or gone."

source=npe;local_knowledge

"I traced this from a map. I know the feature is still there and that 
my tags are correct."

source=landsat

"Hey, if you can get a  better source, please change."

source=interpolation

"I went there but guessed the outline (buildings, sports pitches, ...)"

Mike