Consistency provides a map with balance. It enables features to be perceived as being organised into groups and it allows maps themselves to belong to a family of products through a shared identity.
For a family of products or for a web map stack - a suite of styled maps to cover a set scale range - a degree of consistency in feature styling allows the user to maintain a sense of location awareness and scale. As well as being aesthetically preferential, a consistent approach can also put the user at ease.
Consistency also leads to effective communication through the concept of familiarity. If the same symbol is used repeatedly to depict the same feature, then once the user understands what that symbol represents they can recognise it immediately thereafter. Familiarity breeds confidence.
Conversely, inconsistency can lead to confusion and poor communication of the maps intended message.
Example
Ordnance Survey’s common map styling
This work was started in 2010 and aims to provide a consistent look and feel to all products and services as required. A consistent colour palette is the most immediately noticeable commonality but symbols and font families are also consistent across the portfolio. The idea is that users not only become familiar with the various representations of features but are also able to recognise an Ordnance Survey map at a glance.
The consideration of a colour palette is key to even the quickest of map designs and is often aligned where possible to corporate identity.
Larger image
The backdrop colour style shown above can be seen in the raster variants of OS VectorMap products, Ordnance Surveys web and mobile services and the map-based search function on data.gov.uk. We also offer a variety of style sheets to support our vector products and this style has become the standard graphical portrayal.
Back to Cartographic design principles.