Geograph - photograph every grid square

Most GPS receivers allow you to change the datum and display format to OSGB36 and British National Grid, the convention used by the Ordnance Survey of Great Britain. If you're using a GPS built into a mobile phone, this may not be possible, and your coordinates will always be in WGS84 lat/lon format. If you also use your GPS phone to take your geographs, it should store the positions in the GeoExif header, which Geograph should interpret correctly as camera position.

Otherwise, you can use the Google map part of the submission routine ('locate/find on map') and enter your lat/lon coordinates in the format 'loc:N51.7252,E0.5905' in the box below the Google map. This will look up the grid reference for the location and insert it as _subject_ position into the submission dialogue. You may have to adjust this unless the subject was right in front of you.

Alternatively, there is a conversion tool here on Geograph Tools http://www.nearby.org.uk/coord.cgi?f=conv from which you can copy and paste. There's also a bulk conversion tool on the Ordnance Survey website http://gps.ordnancesurvey.co.uk/convertbatch.asp?location=0 which will convert lat/lon co-ordinates into grid references, although this uses a slightly different datum for the lat/lon base and will produce a small error (insignificant for Geograph purposes).

(Question asked by Roga and answered by barryhunter, oasthouse and DHL on the forum http://www.geograph.org.uk/discuss/index.php?&action=vthread&forum=18&topic=13483&dontcount=1&page=0#1 )