I’m currently writing a chapter on projections to be published in an upcoming book. I’m seeking submittals of maps for potential inclusion but WITH THE CATCH that you have to tell me how you went about choosing the projection for the map. This is to teach people how we cartographers pick a suitable projection based on the following variables: map purpose (which informs the distortion in area, angle, distance, and direction that we are willing to compromise on), scale, directionality (east-west, north-south), map user familiarity with the projection, and location (poles vs. equator for example).
Not all of these aspects need to be addressed in your particular choice of projection, but at least a few do need to have been involved in your decision. The map will probably be published as well, so it has to be non-copyrighted. The map will be published in a very small format, maybe as small as 3″ by 3″ so it need not be detailed or it may be just a piece of the map. I’ll be considering anywhere from 1 to 4 maps and their associated narratives for the book. You don’t have to do the writing, I’ll do that part as long as you can at least list out your decision making process.
Please use the “Contact” link in the right sidebar to email me with inquiries. Thank you!
#1 by Dan Bowles on September 1, 2013 - 8:55 pm
Hi Gretchen
I’d be happy to give you some words and map samples on the Australian mapping standards. ie. most of us are very used to seeing unprojected maps where all the state borders are vertical/horizontal, but across such a huge country this is massively misleading. The standard national projection is the conical Geoscience Australia Lambert, the arguments for which are exactly as you’d suspect.
That said, Australian Geographic has a section titled ‘Lat/Long’ where I do use an unprojected outline of the country and lat/long lines to indicate the place being written about – evoking the idea that we divide space along these imaginary ‘straight’ lines.
For the world we always go in with Winkel Tripel – following NG, perhaps you could get comment from them on that choice.
Another one would be orthographic vs stereographic for polar projection. For no particularly good reason other than that it represents the earth as viewed from space, I always go for orthographic at the poles and anywhere else I’m showing a regional view (ie. smaller than UTM scales) for which there isn’t already a good conical projection. (or if I’m just feeling lazy…)
I bet Bill Rankin from radical cartography would have some great material for you if he’s willing to help.
If you could write about why some projections are so bad, eg. Peters, I reckon it would make for a good compare and contrast type exercise.
Flick me an email if you’d like to discuss further.
Cheers
Dan Bowles
#2 by John Nelson on September 3, 2013 - 10:29 am
Here’s one:
http://uxblog.idvsolutions.com/2012/08/hurricanes-since-1851.html
I chose a south-pole stereographic projection for historic hurricanes. I did it because it was 1) a novel way of looking at a familiar phenomenon, 2) did the best job of illustrating the concept of a rotational ring of storms constantly swirling around the earth, and 3) it provided a better composition than other candidates (there are some also-ran projections pictured in the link) and 4) I am so sick of Mercator (and Plate Carree hurts my feelings). I think, increasingly, when folks in the wild see maps that are not Mercator they look “wrong.” Sometimes the right projection can also surprise, so bonus.
I’m still happy with it even though lots of folks voiced confusion (I’m still convinced this was also an artifact of the darkness of the globe basemap and a too-weak lat long grid reference) and I’d do it again!
Best,
John
#3 by JRigs on September 5, 2013 - 12:26 pm
I don’t have a map to submit, but would like to suggest that you consider including a treatment of dealing with local/grid coordinate systems and some techniques for conversion (eg, using combined scaling factors to create custom PRJ/WKT). Understanding that you are only writing a chapter on projections, this is worthy of at least a mention and possibly recommendations for further reading into the subject. The blank look on faces of green GIS grads when ground/local coordinates come up is getting old.
If I may, the following is a detailed background on this issue:
http://www.ejsurveying.com/Articles/Working_with_Grid_Coordinates.pdf