One question arizes then - what really unprojected Longitude/Latitude is? A projection on a sphere?
Jaromir.
On Wed, 26 May 2004 12:26:49 -0400, <[EMAIL PROTECTED]> wrote:
Your first table is in LonLat (no datum). When you convert a projection that uses no datum to one that does, no datum transformation occurs and conversion error can be up to ~300 meters. If you want accuracy don't use LonLat (no datum).
-Bill
Mail List: [EMAIL PROTECTED] From: on 05/26/2004 04:40 PM ZE2 To: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> cc: Subject: MI-L Projection bug?
I discovered a very strange behavior of MapInfo: I have two tables with a single point in them, first is in CoordSys Earth Projection 1, 0 second is in CoordSys Earth Projection 1, 9999, 10, 589, 76, 480, 4, 2, 3, 1, 0 In both tables the point has the same coordinates: 18.519163,48.52017 When I place both the tables into a single mapper, the points perfectly overlay. But when I change the projection of the mapper to CoordSys Earth Projection 8, 1001, "m", 21, 0, 1, 4500000, 0 Bounds (-3749281.53901, -10002137.4978) (12749281.539, 10002137.4978)
or save copies of the tables with this projection, the coordinates (in meters) are different! First table: 4316739.3,5379336.0 Second table: 4316791.2,5379340.9 The distance of the points is 52 meters then! The first pair of coordinates seems to be more close to the reality. I haven't tested it with other projections, so I don't know whether it is related only to discussed ones or other too.
Please help!
-- Jaromir SVASTA Hydrogeologist Geological Survey of Slovak Republic Mlynska dolina 1 917 04 Bratislava Slovak Republic
Tel: +421 2 59375326 Fax: +421 2 54771940
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-- Jaromir SVASTA Hydrogeologist Geological Survey of Slovak Republic Mlynska dolina 1 917 04 Bratislava Slovak Republic
Tel: +421 2 59375326 Fax: +421 2 54771940
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