Thanks for the comment, Anu. This one-degree globe itself does not comprise 8 orthographic-octant cutouts (90 degrees. wide), but conventional gores that are 10 degrees wide, plus a pair of polar caps. However, when designing the Cahill-Keyes map as a grad student back in 1975 ff, I used a lot of orthographic globe printouts, all with 5 degree graticules, in sizes of 5", 10", and 25", from R.L. Parker's Supermap program (on punchcards!) These were to visualize and illustrate the C-K approach, but the graticule of the Cahill-Keyes is not orthographic. The image below is a paper-cut-and-paste (real scissors, real paste), part of a supplement in my 1978 Ph.D. dissertation: (orthographics reduced by photocopier from 5-inch, 5-deg. originals):
And this was another visualization, to show the Cahill-Keyes octants from all viewpoints on 26 orthographic projections:
But as mentioned above, the graticule of the Cahill-Keyes is not orthographic; see http://www.genekeyes...ing-Cahill.html. As I stated there in part,
In my re-working of Cahill, I wanted all adjacent geocells to be reasonably similar in size to each other. Not perfectly, of course; squashing a sphere demands compromise. Inner geocells of a Cahill-Keyes octant are smaller than outer ones. But the change is gradual, and no geocell is grossly out of whack with its neighbors. For me, this is an essential criterion, because I want the 1/1,000,000 Megamap not to have bloated geocells next to more normal ones. And I want the entire array of geocells closely resembling its globe-parent.Therefore, the Cahill-Keyes design is sui generis. It does adapt Buckminster Fuller's Dymaxion map principle of having nominal globe scale along the outer edges of a facet, and shrinkage toward the middle. But in addition, unlike Fuller, or any other world map, its controlling desideratum is to keep neighboring geocells as similar as possible. (See "Photos of the Cahill-Keyes Megamap Prototypes", esp. Figs. 3, 6, and 7.) Consequently, its inner projection matches none of Cahill's three Variants.("Projection" is not quite the right term here; "transformation" is closer.) Perhaps we could dub mine the "Proportional Geocell" or "Global Cognate" world map design.
In other words, the Cahill-Keyes is a unitary world map in its own right, not an orthographic, just as the C-K globe is made (by Roubal, to my design) in the manner of conventional globes, and likewise not an orthographic.