And in my haste I omitted to thank Chippy for his excellent map rectification/warping and WMS facilities. Apologies Tim.
Cheers Andy >-----Original Message----- >From: Andy Robinson (blackadder-lists) [mailto:[email protected]] >Sent: 06 October 2009 3:04 PM >To: '[email protected]' >Subject: Announcement - OS 1:25k mapping availability for OSM data >contributors > >We are all used to drawing in difficult or far away features by referring >to the NPE 1" to 1 mile out of copyright Ordnance Survey mapping in JOSM or >Potlatch. Its great for long linear features but for accurate stuff, like >field boundaries and detailed information about the landscape, especially >in rural areas, it's not enough. > >Enter the OS 1:25,000 scale (two and a half inches to the mile) >1st/Provisional edition [1]. Which I'm happy to announce is starting to >make an appearance for the project. > >There are two parts to the availability currently. One focused on providing >it via WMS for use in JOSM and the other as tiles for Potlatch. > >The first full sheet (NX88 NW or Dumfries [2]) is available for you to try >out in JOSM [3]. Just add the URL as a custom WMS. > >For the Potlatch tiles RichardF has worked up some code magic that should >automate the process of rectification and tiling. It may take me a little >time to get that running and the tiles will probably be served from the new >dev machine which is not quite ready yet so there will be a further >announcement on this. > >Both the WMS and google format tiles use the same rectification data. > >The time consuming part is manually obtaining the pixel co-ordinates for >the corner gridlines of each sheet (which I have to scan in two halves on >my A3 scanner). It has to be done manually to get the best accuracy, which >should be generally 10m once available in Potlatch or JOSM. i.e. >significantly better than was possible with NPE, though note that its still >only as good as the OS originally survey it in the late 19th century. >Anyway, it means that this part is a slow process. > >Currently I have around 15% of the published sheets with more arriving >every day. More would be welcome, either by way of donated maps, scans, or >funds to purchase more from retail suppliers (higher cost - usually about >£3 to £8 each). With 2027 sheets in the series cost is a factor for how >quickly I can grow the set. > >I'll keep the index updated on the wiki with progress (both obtaining and >scanning/tiling) so look out for your area turning up. The majority of the >sheets I have are for England and Wales. Scotland never had full coverage >from this series. > >Cheers > >Andy > >[1] "http://wiki.openstreetmap.org/wiki/Provisional/First_Edition"; >[2] "http://osm.org/go/e...@6r"; >[3] >"http://warper.freemap.in/layers/wms/1?request=GetMap&version=1.1.1&styles= >&format=image/png&srs=epsg:4326&exceptions=application/vnd.ogc.se_inimage&" _______________________________________________ Talk-GB mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-gb
