Have you ever wondered how our dedicated team of cartographers find the changes that they need to update on a piece of mapping data? When our 300 or so surveyors are out on the ground (or in the air) capturing changes to the landscape, it isn’t only the updated information that is supplied to the cartographers, they have to check an entire ‘chunk’ of data to find any changes.
Our cartographers manipulate and enhance the core data provided by our collection teams to produce our paper maps and small-scale data products. I’m sure you can imagine that it takes a fairly specific set of skills to do this – so do you think you’re up to the task?
Have a look at our before and after shots below. The top set has only one change, but the bottom set has six changes.
Can you find them all? Leave a comment saying where you think the changes are and we’ll reveal the answers later today.
Six changes between these next two:
Our cartographers do the job by working with the ‘before’ picture, also known as the current version of the map. Then they overlay the current map with a detailed visualisation of OS MasterMap, showing the very latest information from our surveyors. Our cartographers then compare the two maps, or data extracts, to identify features need to be added to a new version of the map. While doing this, they also have to think about the product specification for the map they are updating, as not all maps will need to include every detail from the OS MasterMap visualisation.
On their own, some of these minor changes may not have been included in a new version of the map as they wouldn’t meet the revision criteria, but if other changes are being made to an extract, it is more efficient to make these minor changes at the same time.
And how would you feel about playing a daily game of spot the difference where you don’t know how many changes you’re looking for or how big or small they might be? If that sounds like the job for you maybe you’ve got the attention to detail needed to be an Ordnance Survey cartographer!
Don’t forget, leave a comment if you think you can spot all the differences and we’ll reveal all later today.
How did you do?
See the answers below with the changes our cartographers made: