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OSTN02 and OSGM02 for Developers

We are pleased to make OSGM02 and the OSTN02 and OSi/OSNI Polynomial transformation models available to software developers for incorporation into their software. An increasing number of popular software packages will include these transformations, which can be recognised by the Ordnance Survey logo with the text 'OSTN02, OSGM02 and OSi/OSNI Polynomial enabled'.

The models can be incorporated in three ways: 

(1) Use the dataset below, which includes the grid of transformation parameters, the procedures/equations to use, a worked example and some sample files for testing. A style guide and technical information are also included.

Download transformation dataset (14.5 MB)

(2) The grid of OSTN02 parameters from the zip file available above has been converted to the NTv2 format which is popular with some GIS systems. 

(3) A Windows (XP/Vista/Windows7) dynamic link library (DLL) of the transformation, which can be incorporated directly into software,

Download transformation DLL

It is is available as part of our Grid InQuest application.

This software is licensed pursuant to the terms of the BSD Licence.

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For general enquiries, complaints, feedback or suggestions, email: customerservices@ordnancesurvey.co.uk or call us on 08456 05 05 05