[OSM-talk] Announcement: Availability of True Offset web service

Dermot McNally dermotm at gmail.com
Fri Feb 18 00:21:31 GMT 2011

On 18 February 2011 00:08, Ben Last <ben.last at nearmap.com> wrote:
> Quick question; how does this cope with updates to aerial/satellite imagery
> that may change the offset for a given service at a given location?

In exactly the same way as, say, the Offset bookmarks offered by JOSM
- it doesn't, and the mapper needs to notice that the imagery doesn't
seem to line up any more. As such, as a baseline, using True Offset is
at worst no worse than other options for managing your calibration.

Though in fact, because the correction factors are maintained by the
crowd, the story is actually likely to be more positive than that.
With private offset bookmarks on JOSM, each individual mapper needs to
notice the change and recalibrate, hopefully doing an accurate job.
With True Offset, the first mapper to notice the change can update the
stored offset. Others may fine-tune it. Everybody else just keeps
mapping without noticing any change.


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ja ma oma ei leiagi üles

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