At 05:26 PM 10/8/2007, you wrote: >I just did a GPS track of some roads, and uploaded it. Now I see it on >the main map, it seems that the roads are consistently few metres north >of where they are on the Yahoo aerial imagery. Do I move them to match, >or do I trust the GPS over Yahoo (i.e. are the Yahoo images offset a bit)?
If your data deviates from the Yahoo images only for part of the track, then I would say to correct the data. But if it is consistently off you might want to verify against a different image source. I have read that Google maps can be off by some distance. I don't know about Yahoo maps. If you are in the USA, you can download a free program for Windows (assuming you use Windows) and view your track data from a GPX file as an overlay to USGS topo maps, photo data or higher resolution photo data which is only available for the largest cities. I have done a little comparison of my collected data to the USGS images and the correlation seems to be pretty good. Regards, Rick Collins _______________________________________________ newbies mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/newbies
