How can we get our map colours right? How open journalism helped us get better

How can you get the colour scales right on maps? It's something we spend a lot of time thinking about here on the Datablog - and you may notice a huge variety of ones we try out. This isn't just design semantics - using the wrong colours can mean your maps are completely inaccessible to people with colour blindness, for instance and actually obscure what you're trying to do. It's distinct to problems expertly faced by the Guardian graphics team - who have a lot of experience of making maps just right. But on the blog, making a Google Fusion map in a hurry, do we get it right? It came up this week with this map on poverty and deprivation in London , part of our London: the data series. Recently we've been using the colour scale on the map below, which is a variation on the famous traffic light collection of colours - for the Guardian, this tends to go from green, meaning good, or low - up to red, meaning bad or high. It's used by map makers and newspaper designers all the time. But is it any good? This sparked a debate on Twitter, with Gregor Aisch of Driven by Data weighing in on the weaknesses of the colours we chose. It led to a big conversation - and a mutual editing of the map's colours. Below is a Storify showing how the conversation evolved - to create a better map. But, is it good enough - did we get it right? You tell us in the comments field below - and share your perfect colour schemes too. [ View the story "Making a map - together" on Storify ] NEW! Buy our book • Facts are Sacred: the power of data (on Kindle) More open data Data journalism and data visualisations from the Guardian World government data • Search the world's government data with our gateway Development and aid data • Search the world's global development data with our gateway Can you do something with this data? • Flickr Please post your visualisations and mash-ups on our Flickr group • Contact us at [email protected] • Get the A-Z of data • More at the Datastore directory • Follow us on Twitter • Like us on Facebook