Thu Mar 03, 2022 13 Projections for 2022 (Part 3)
A collection of my own experiments
(see Intro for further explanations)
|Original Creator||Nedjeljko Frančula / Frank Canters (1971 / 2002)|
|Remarks||A fusion of Canters W09 (northern hemisphere) and Frančula XIII (southern hemisphere).|
|My variation||Developed in 2021, presented here for the first time|
This year’s calendar is about my experiments, and sometimes experiments go wrong.
Here is a projection that might not be complete failure, but it does have a certain imperfection.
It is a fusion of two existing projections, both are optimized variantes of Wagner IX.i: Frančula XIII and Canters W09 (see also my blogposts about the Frančula and Canters projections). I like them both; but it occurred to me that the distribution of angular deformations on the landmasses of the southern hemisphere is a bit better – and in contrast, the Canters W09 shows a few advantages on the northern hemisphere.
Regarding the distribution but areal inflations on the continents the two are not much different, although I do see slight advantages on the Frančula.
So I thought: Take the best of both worlds (pun intended), paste the northern hemisphere of Canters W09 and the southern hemisphere of Frančula XIII together! For both, a little adjustment of the aspect ratio was needed to make them fit together at the equator: The Frančula was a bit compressed in east-west-direction, the Canters a bit stretched. The result is shown above.
But although I like this composition visually, I have to admit that it is not without flaw. Look at the isolines of angular deformations and areal distortions:
The isolines are given for max. angular deformation of:
10°, 20°, 30°, 40°, 50°, and 60°.
For the areal inflation, shown normalized to the value at the central point of the map, the lines represent values of:
1.2; 1.5; 2.0; 2.5; 3.0; and 3.5.
You can see that the lines are broken – there are discontinuities in the distribution of distortions at the equator. Such discontinuities are not unprecedented, in fact they occur in various fused projections: To name just a few, McBryde S3, Goode’s famous Homolosine and the wonderful Philbrick Sinu-Mollweide … all of them are fusions, and they all show discontinuities in the distortions.
My first idea was that the Canters-Frančula might be a nice addition to the calendar,
but, because of the discontinuities, not good enough to add it to the list
on my website … but then I thought that if such well-known, beautiful projections
are “allowed” to have them, than I can allow them, too, on my own experiments.
And thus, the Canters-Frančula projection will be added soon.
Next month, we’ll have… ummmm… April.
References / Footnotes
- ↑ Nedjeljko Frančula: Die vorteilhaftesten Abbildungen in der Atlaskartographie (German)
Small-scale Map Projection Design.
London & New York 2002.
- ↑ McBryde S3 is a fusion of the sinusoidal projection and McBryde-Thomas Flat-Polar Sinusoidal, joined at 55°51′N/S; Goode’s Homolosine fuses sinusoidal and Mollweide at 40°44′N/S; Sinu-Mollweide also combines the latter two, but at 40°44′S (before rotating the map center).
My 2022 Map Projection Calendar
To read another part of my 2022 map projection calendar series, select the desired month.