Test Coordinate system conversion

British National Grid (WKID:27700) to WebMercator (WKID:102113)

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RED CIRCLE - British National Grid Point added on the top of WebMercator base map - you can notice the shift of aproximately 147 meaters to the east and 11 meaters to the north.



The direct project function of ArcGISServer 9.3.1, 10.0, 10.0.1 is not returning the correct values of new coordinates, however it will change when version 10.1 is released.

GREEN CIRCLE - British National Grid Point added on the top of WebMercator base map and reprojected to WGS84 with Helmert transformation using custom Java Script functions.





Add new British National Grid Point:
Easting:    Northing: