Play spot the difference with our Cartography team
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.
The original
Spot any differences?
Six changes between these next two:
Original
And updated
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:
Themocracy
Map extract no 1, New school building, running in a N-S direction near map centre.
Extract 2, Lettering removed from below the word Lane at E edge of map, changes to field (subdivisions) to N of Craft centre, and NC woodland symbol reduced to 1 tree. W side of M’way (inside junction, NC woodland symbol reduced, pond added. New buildings added in extreme NW corner of extract. New building added to E of schools boundary. and new building added inside school field on E side of existing buildings
First set: difference is near the small right of way just to the West of the Westmost school. There is now a fence or wall between that and the school. But it looks like you can’t get anywhere by following the path!
Second set: There is now a pond in the middle of the big roundabout instead of some trees.
Just to the East of the big roundabout the field boundaries have changed.
Top left corner, the buildings and fencing configuration has changed.
New building just West of the South end of the motorway junction.
New fence configuration near the pond on the right.
New building right of school.
Top set – the bottom school building is a rebuild.
Bottom set
1)School building has been demolished
2)Building south-west of the large roundabout has been demolished (most likely mapped incorrectly first time around)
3)Building SE of the roundabout & NW of the school has been demolished
4)Top NW of the tile – changes to housing estate
5)Within the large roundabout pond removed
6)East of the “20″ internal fencing removed
Top map: south-most of the 3 schools has been re-modelled.
Bottom map: (1) new pathway through top-left housing estate; (2) school building has gone; (3) new building in the corner of the open area west of the motorway; (4) landscaping in the west side of the motorway junction roundabout; (5) field boundaries changed to ?farm just east of the junction; (6) field boundaries added just by the big 20.
Not sure if (5) and (6) count as 1 thing and there’s another to find!
Nice game, thanks for posting it!
Just one comment – were you intentionally naming the files so a mouseover would drop a massive hint about the best places to look?
Even if not, I enjoyed playing
Adam, to save face, I’ll say yes! Answers coming up shortly for those who’d like them…
OK, granted I missed #2 in the second map but there are also DEFINITELY changes to the houses up in the top left corner.
I missed no 6 but definitely changes in top left corner