katpatuka's diary
still so many unmapped islands in Indonesia and Oceania...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...
Coordinates:Posted by katpatuka at Tue, 03 Nov 2009 07:57:04 +0000 in English (English)
Comment from daveemtb at Tue, 03 Nov 2009 09:09:24 +0000
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 at Tue, 03 Nov 2009 09:09:57 +0000
PS also see http://wiki.openstreetmap.org/wiki/Coastline_error_checker for info.
Comment from katpatuka at Tue, 03 Nov 2009 09:53:22 +0000
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...
