A darker version of the light grey canvas basemap promises to expand ArcGIS Online users' available map palette when creating online mashup maps.
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One of the new things that’s coming along is the new dark grey canvas map. Currently, a light grey canvas map is one of 9 available basemaps that's available for users of ArcGIS Online. This is a clean and simple basemap that contains only the most basic of information and labels and is ideal for mashing up with a thematic layer that requires a wide range of colours. Its minimalist approach allows the mashed up thematic data to really stand out.
Figure 1: A sample mashup map using the currently available light grey canvas basemap
The dark grey canvas map works in a similar way. It contains the same amount of labels and information as the light grey canvas map except that, of course, it's darker. The dark grey canvas map will allow data that's symbolized with lighter colours to stand out better. Esri’s Urban Observatory uses the dark grey canvas map effectively.
Figure 2: The same mashup map using the beta dark grey canvas basemap
The dark grey canvas map is still in beta and is only available for the smaller scales. Take it out for a test drive and provide Esri with your feedback.