On 9 September 2013 20:05, Lester Caine <[email protected]> wrote: > I'm currently playing in an area where the highest resolution imagery is > still an older view, while as I zoom out we step to newer imagery which is > some distance off from the map tracks. I'm fairly happy with the map as I > have had some older gps tracks which it follows, and I'll run over in the > morning and gather a new track as a cross reference, but are people in > general finding that these new images are out of alignment with what is > currently mapped? Can I assume that they need realigning before using them?
I find that current BIng is usually mis-allgned by two or three metres relative to OS StreetView, which I believe is good to better than 1 metre. One reason for this is parallax error, because the images aren't taken square on to the ground (that may be because the camera is taking in quite a large area. You can see this with building, you can end up with a metre or more difference depending on whether you use the top or bottom of the building. It also presumably means that alignment changes with the height of the land. On the the other hand, individual GPS points usually have larger error than this. With commercial grade GPS, you probably need several hours averaging to get down to a metre accuracy. _______________________________________________ Talk-GB mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-gb
