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OS Net support

Surveying with OS Net free services

These guidelines are intended for surveyors who are acquainted with GPS surveying. We outline the national coordinate systems in Great Britain, describe the national positioning infrastructure and much more.

Surveying with OS Net free services – an overview

Learn why OS Net is so important, and what the RINEX data server and online coordinate transformer do.

OS Net accuracy

Find out just how accurate OS Net is, expressed as standard error distances in metres.

Antenna phase centre offsets

A GPS baseline is measured between the phase centres of two antennae. Find out the various antennae and offsets currently used in the active network.

Spreadsheet for coordinate calculations

Our coordinate calculations spreadsheet enables you to carry out common calculations with coordinates. It includes a full set of Transverse Mercator projection functions.

A guide to coordinate systems in Great Britain

Learn about the concepts of coordinate systems to help you use coordinate data and mapping coordinate systems in Great Britain.

View or download

Glossary

Understanding the meaning of technical terms relating to OS Net and global navigation satellite systems.

 

 

Grid InQuest coordinate transformations software

Grid InQuest transforms between the ETRS89 (WGS84) and OSGB36 National Grid coordinate systems using the same transformation models (OSTN02/OSGM02) as the online coordinate transformer. OSTN02 and OSGM02 for Developers

Coordinate batch converter file formats

The coordinate batch converter accepts a plain-text (ASCII) file in a simple format, with one point per line. There are four coordinate types; learn about them and how you should code the text files you upload.

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.

OSTN02 data in NTv2 format

Since the plane grid form of OSTN02 is not easily compatible with some GIS systems, some of them systems utilise a transformation data format known as NTv2.  We are pleased to provide a download of OSTN data in NTv2 format.

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