Bonjour Paul, and all osmers Let me summarize the situation regarding NRCan-Canvec data.
Good news... - about a thousand files (maps) are brand new around Ellesmere Island - Road network is updated every year for most of the provinces Old stories... - YK,NT,NU were checked for changes about 10 years ago using 20m resolution imageries. Some areas were updated using this imagery. - We are replacing some of our hydrographic network with provincial data (BC was the first replaced). It is usually more than 10 years old , our is older than 25. Much older stories... Actually, the rest of the NRCan-Canvec content is older than 25 years (average 30, older 64). It concerns southern Canada... - Buildings, railroads and other structures (obviously) - Vegetation (wooded areas) - could soon be replaced with a 5 year old automated classification using 30m imagery - Wetlands - Built-up areas You should not be surprise that some features are not up-to-date... I know that I've already done this exercise before but it is important that the community is aware of the limitation of the data. This is the same for all NRCan digital product (Canvec, Toporama, ...) and worst for paper maps :-( As mentioned in another email, the main objective of providing the Canvec.osm product was to help the community to focus on updating available data instead of recapturing everything from scratch. And from there, eventually use it to update our products. Since then, as a lot of Canvec data was imported, and updated ... - we now use OSM data for changes detection (it help us planning GPS field campaign for road updating in some provinces) - we are looking at using OSM data to help us updating the entire Canvec Product! It looks like a win-win situation for me! Best regards, Daniel Note: If anybody think this information should be added to the Canvec wiki page, you can use the above information -----Original Message----- From: Paul Norman [mailto:penor...@mac.com] Sent: April 17, 2012 05:00 To: talk-ca@openstreetmap.org Subject: Re: [Talk-ca] Canadian imports: good or bad? > From: Ian Bruseker [mailto:ian.bruse...@gmail.com] > Sent: Sunday, April 15, 2012 9:31 PM > To: talk-ca@openstreetmap.org > Subject: Re: [Talk-ca] Canadian imports: good or bad? > > On 2012-04-15, at 6:37 PM, Steve Singer <st...@ssinger.info> wrote: > > > I also feel that not of all data sources are equal. Even within > > Canvec some layers are excellent (ie roads and lakes in most of the > > country) while others are often so out of date it isn't worth the > > time to import (ie buildings in much of Southern Ontario) > > > That's the third mention in a row of bad building data in Canvec. I'll > chime in on that to say I found a hospital in St. Albert, Alberta that > was marked as having come from an import. The hospital hasn't been > there for 20 years. The new building is several kilometers away. Not > just bad, full on dangerous if someone actually believed the data in > OSM and tried to find help when they were hurt. :-( I thought it was just BC but it sounds like it's everywhere. Would I be correct in summarizing the opinions so far as 1. The buildings data from CanVec should not be imported unless it can be verified against imagery, in which case you might as well trace the buildings from imagery. 2. There is not a consensus among the community that CanVec data can be imported without verifying the data for internal consistency and where possible against imagery. _______________________________________________ Talk-ca mailing list Talk-ca@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-ca _______________________________________________ Talk-ca mailing list Talk-ca@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-ca
