[talk-ph] Be careful in tracing from Bing Maps

Eugene Alvin Villar seav80 at gmail.com
Wed Jan 5 18:03:06 GMT 2011

Hi guys,

Please be careful in tracing from Bing Maps aerial imagery. It is
known that some of the imagery is not aligned to the correct position.
To show an example, please see this Bing maps screenshot: [1]. The
image shows the boundary between two satellite imagery. The imagery on
the top covers Metro Manila is is for the most part correctly
positioned. The imagery at the bottom covers parts of Cavite, Laguna,
Batangas, and Rizal[3] and is *not* positioned correctly. Notice that
the residential streets do not line up.

In order to avoid the misaligned imagery problem that has been
plaguing contributors in Google Map Maker, please try to align the
imagery to GPS tracks or known good data before tracing.

In Potlatch 2 and Merkaartor 0.17, the imagery can be moved by
pressing down the spacebar then dragging. I don't know how to do this
in JOSM but it also has a way to move the background image.

[1] http://wiki.openstreetmap.org/wiki/File:Bing_misalignment_in_Daang_Hari_-_Bacoor.jpg
[2] http://www.openstreetmap.org/?way=28738861
[3] http://www.openstreetmap.org/?way=87284547

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