On 13 Sep 2009, at 22:41, Thomas Wood wrote: > These maps are already rectified of course, it's usually good to > convert the OS coordinates to Lat/Lons and then set the grid corners > as reference points.
But my photographs of the maps will have introduced some tilt and other distortions, so it does need some control points. Possibly you are saying that I can calculate the control points from the OS grid references for the corners. That may indeed be true. > Quite a few sheets were done this way for Oxford. See > http://warper.geothings.net/layers/7 for an example of what's > possible. Very nice. Regards, Peter > > > 2009/9/13 Peter Miller <peter.mil...@itoworld.com>: >> >> I was lent 65 first-edition 1:500 OS maps of Ipswich dating back to >> 1882 a couple of days ago which I have now photographed and uploaded >> to Flickr. I was surprised to find that there was no Flickr group of >> out-of-copyright OS maps so I created it. >> >> The rules I have created says that all maps should be geo-coded, that >> the photos should be released CCBYSA and that the contributor agrees >> that the images can also be used to derive mapping for OSM (to cover >> use under ODBL where there derivation from CCBYSA is less certain. >> >> The group is here: >> http://www.flickr.com/groups/1192...@n24/pool/ >> >> I have also just rectified one map using Warper. Four control points >> seemed to do the job very well. >> http://warper.geothings.net/maps/preview/1205 >> >> If anyone has any suggestions about adjusting the rules for the group >> or wants to be an admin then please let me know. >> >> >> >> Regards, >> >> >> >> Peter >> >> >> >> >> _______________________________________________ >> Talk-GB mailing list >> Talk-GB@openstreetmap.org >> http://lists.openstreetmap.org/listinfo/talk-gb >> > > > > -- > Regards, > Thomas Wood > (Edgemaster) _______________________________________________ Talk-GB mailing list Talk-GB@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-gb