On 18/07/07, Thom Shannon <[EMAIL PROTECTED]> wrote: > > > Apologies if this has come up before. But what are the arguments/reasons for > using the aerial photography or making GPS traces. Is the accuracy of either > much of a problem? Or is it just that the photos aren't so high-res in > certain areas, or outdated, so GPS is better. >
For GPS: - GPS was around first before we were allowed to use Yahoo. - Yahoo does not cover everywhere, as you say - GPS is a record of where you went (useful for linking photos to places etc) - GPS lets you map things not immediately obvious from Yahoo, ie: foot paths in the country side For Yahoo: - GPS is sometimes not very accurate (ie: built up areas) - here it's easier to trace - you don't have to go down *every* road -- you just get the name and map the extent by tracing -- you have to be careful not to miss foot paths and side roads though - it's easier to put in area features such as park/lake boundaries from Yahoo. - you can even get some things like building outlines (for hospitals, stations prisons etc) - you can map some things in places you can't actually go.. mostly this isn't very useful, but it makes the map look pretty :-) I mostly use Yahoo, but I always carry a GPS collecting a track log anyway. That way you get the best of both. Dave _______________________________________________ Talk-GB mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk-gb
