I thought it was very interesting to look at the OS and OSM overlaid on each other on the WMS link someone posted.
1. I was very impressed with how really accurate OSM is compared to OS where I know it has been done systematically 2. I was disappointed to see how out of date the OS data is - streets which I know personally have been there for two years still aren't in the OS data - but it's not all that out of date, some recent streets are there. 3. OS street detail has some real problems where a street is closed off part way along - streets where there is a bollard or a section of footway between street ends look like they are continuous streets on OS where I've looked (maybe this will be better in the vector stuff to be released). No wonder we get these tales of trucks following satnav only to end up stuffed. 4. I'm disappointed how many street names are missing on OS, especially short ones (short street not short name). Mapnik is a much prettier rendering as well, IMO. While I agree with Tom and Jonathan about tracing putting people off doing the base level survey, I have found that where the basic street level survey has been done properly, people will make small corrections from local knowledge and quick checks and surveys, where they aren't prepared to spend a whole day doing something. Quality has improved in most areas I've done over time (though it's still clear to me that we are very poorly represented in very rural villages). I'm not sure tracing is quite so problematic as from satellite, because OS has street names as well, but someone is still going to have to go back and get detail and check it (otherwise what is the point - if all we are going to do is trace OS, the user might as well use OS in the first place). I think one of the problems of this completeness is people don't know. Now I know Harlow needs attention I might well put it on my list for a visit. We did that for King's Lynn where we had the street pattern but no names and no other detail (though we've not finished yet), but only because I looked carefully at what had already been done. Personally I don't see the attraction of just sitting for hours in front of a computer duplicating someone else's product. For me the interest in OSM is the exploring, the wind in my face, the exercise. I think it's actually a shame that if people start tracing everywhere we can't say this is the fruit of our own labours. I'd still really like to complete Cambridgeshire by surveying. At 93%, we're so nearly there, and I'd really like to be able to say yes, *we* did it. Where I think I'll use the OS base most is if I miss a street name by accident, and will save going back to check it. But poersonally I won't be spending yet more time at my computer mindlessly copying. David _______________________________________________ Talk-GB mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-gb
