OpenStreetMap
still so many unmapped islands in Indonesia and Oceania...
Posted by katpatuka on 3 November 2009 in English.There are still so many unmapped islands in Indonesia - did PGS miss them? I managed to add the group of Sangir Islands (http://osm.org/go/4pMkDwX) tracing landsat images using josm but yesterday I again found Togian Islands being unmapped...
Discussion
Comment from daveemtb on 3 November 2009 at 09:09
In my experience PGS is quite inaccurate and often misses small islands and islands where the contrast isn't very high. It can also get confused with marshlands. Alternatively, someone may have deleted them accidentally. (or worse...)
It's great that you can map these islands :) On Osmarender it looks as though there could be a problem with the direction of the coastline, though I guess you may have already fixed this.
Have you seen the coastline error checker? Check out http://dev.openstreetmap.nl/coastlines.html?lat=3.553&lon=125.71&zoom=10&layers=B00T
Comment from daveemtb on 3 November 2009 at 09:09
PS also see http://wiki.openstreetmap.org/wiki/Coastline_error_checker for info.
Comment from katpatuka on 3 November 2009 at 09:53
Thanks. I know the coastline error checker well - I had to consult it 'cause a am so used to trace lakes (lake on left side) that I started to draw the islands in the same direction before noticing the wrong direction (josm's validator should mark that as 'error' - not as 'other') Checker's last update is from yesterday...