[Talk-gb-midanglia] [Spam] High volume changes round Cambridge

[David Earl]

On 23/12/2008 13:56, Rowland Shaw wrote:
> I do think that there needs to be greater understanding on the
> limitations of civilian GPS -- whilst they may give a position to a
> silly resolution, they're only ever going to be accurate to 6m or so

and that's not dissimilar from the Yahoo imagery.

The problem is that the Yahoo is only displayed two zoom levels out from 
amx, so the accuracy with which you can place points is abysmal. And add 
to that that it depends on the accuracy of the alignment and projection 
in Potlatch which most of us have found rarely matches GPS traces which 
tend to agree with each other.

Looking at these changes we now have serious kinks in roads and 
especially the Guided Busway which I know are straight. This is because 
you can't trace in Potlatch to the accuracy needed at the zoom levels 
when satellite imagery is displayed.

David