In an earlier post of mine I commented about a blog post by John Krygier about Edward Tufte. I can now proudly present part 2;
Commandment 4: Minimise Map Crap
Map crap is everything that gets in the way of the purpose of the map. John points the finger at Big, honkin’ north arrows, fancy borders, fake 3-D effects, and black graticules (they should be grey or another subtle colour). As it happens with Google Earth all of these are provided by the program with little or no control given to the user, except 3-D effects. So apart from the use of 3D (discussed here), map crap isn't a problem that has transferred from static maps to Virtual Globes.
John's opinion is that for a map that is for advertising, promotion or fun map crap has a place because a minimalist map is austere. He has a point but if the map crap gets in the way of the central message, it needs to be removed.
Commandment 5: Map Layout Matters
This is a big topic in virtual globes. IMHO Authors of Google Earth Projects have a responsibility to set up views in which certain layers are turned on, some are turned off and a certain camera viewpoint is taken, I call these 'picture frames'. They help the user 'get' the message of the project whilst not stopping him/her from exploring the data themselves to see if they agree with you, an advantage over a static map.
John thinks its an issue for static maps too but says its too abstract a topic to encapsulate in a short post. I think he's right, getting layout correct is where map making drifts away from science into art.
Commandment 6: Evaluate your Map
This is the one area I really haven't covered yet in this blog; the importance of user testing. My view is mostly inherited from Steve Krug (related interview) in 'Don't make me think'. His points were written for commercial web pages but they apply just as well to Google Earth projects;
- Test with users early in a project and often
- Quick and dirty testing will find the big problems with your project
- Quick and dirty = 3 typical users for 1 hour looking at your project
- Just sit with them while they navigate your Google Earth project prompting them if they get really stuck asking lots of 'what are you thinking now?' questions.
- Analysis of the test should also be quick, if a report is needed a side of A4 is enough. Avoid longer tests as this cuts into the ability to test frequently.
John also discusses evaluation by peers (getting people around you to comment on your work) and documentation of design. I think for Virtual Globes neither of these are anywhere near as useful as user testing because the technologies are so new. You may have produced a well documented project that all your colleagues but find that it sucks as far as users are concerned. This is because there are no norms of what a Google Earth project should look like at the moment, as the Geo Web develops this time will pass, norms will appear and peer/documentation based evaluation will become more important.