Hi guys, With all of the new Bing imagery that's available, I'd like to remind everyone to be careful with unaligned Bing imagery.
Here's an example showing how two different satellite images are not aligned with each other (look at the LBC roof sign): http://mvexel.dev.openstreetmap.org/bingimageanalyzer/?lat=14.517377504551362&lon=121.00218251959474&zoom=18 Obviously, one (and likely both) of the images is not positioned correctly. This shows that Bing's imagery (and even Google's) is not always aligned or positioned very accurately. There may be an offset of up to 10 meters. If there are multiple GPS traces in the area, you should use them to align the satellite imagery first before tracing buildings, roads, and other features. You can average multiple GPS traces to get a good enough positional accuracy and Potlatch, Merkaartor, and JOSM all support manually moving the background imagery to the correct position. If there are no available GPS traces, then it's acceptable to trace the Bing imagery directly. Someone can realign the map later on when GPS traces would become available. For more information, please check out this e-mail that I sent last year: http://www.mail-archive.com/[email protected]/msg02829.html Happy tracing!!! :) _______________________________________________ talk-ph mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-ph
