[Proj] OSTN02 question: GRS80 instead of Airy.
paul-grass at stjohnspoint.co.uk
Mon Oct 30 16:46:32 EST 2006
On Mon, 30 Oct 2006, Roger Oberholtzer wrote:
> Or not. If I change the +ellps=airy to +ellps=grs80, leaving all else
> the same, I see no difference at all.
Are you sure you removed the towgs84 and nadgrids parameters as well?
There should definitely be a difference there. GRS80 and WGS84 are
essentially the same thing at mapping-level scales - that is why there is
no need for datum transformation. My earlier message was a little
Not sure which machine I developed that OSGB36 grid file on so can't check
I'm afraid - it may have been on machine that I no longer have access to.
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