6 replies to this topic

[frax]

Hi,

I was passed this map in a project that I am working on - a graphic designer had tried to assist specialist in delineating marine areas of interest on a global map - but the map is a total mess. Graphically it was ok, but... - yes just look at it. It didn't mark either where the end of the world was, so the marine areas are rectangular out to the borders of the image. And Antarctica. Note: this is not the image I was given, I removed all the delineated areas and labels (the white splotches).

I have reprojected this to Mollweide, which it resembles, but isn't. But does anyone have any tips on what projection it is? I tried the ones in ArcMap, but I couldn't (easily) find the right one (tried to match up the exported continents in Illy).

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[Matthew Hampton]

I'd say it looks rather pseudocylindricalish...perhaps Robinson?

[frax]

Robinson was my first guess too, but Robinson doesn't have that distortion that you see on South America and Australia. Actually, when I think about it, I think it might be something like Mollweide or Winkel III that has been squeezed a bit by the geography illiterate graphic designer...

[M.Denil]

Winkel III? Snyder does not list a Winkel III, and the Winkel I, II and Tripel do not really look like that sample at all: the Tripel, for instance, has curved parallels (albeit with flat poles).

Eckert III, which is vaguely resembles, has round ends that merge smoothly into the flat poles. On this projection the far left end of Antarctica shows a definite angle as the limb hits that pole. This is rather like the Eckert V, and is also like the Robinson.

The northern mass of South America has a shape very much like a Sinusoidal; so an un-interrupted Goodes Homolosine might be a good guess. That one would not be too far from your Mollweide attempt.

I notice that the far western tip of Siberia seems to be attached to the rest of Asia, instead of floating free to the left of Alaska. Now, this could be because someone erased that bit, but England does not look to be on the central meridian, either.
I would try futzing about with placing the central meridian a few degrees east of Greenwich.

My first try would be an un-interrupted Goodes Homolosine with a central meridian at 13° east: about Berlin.

M.Denil

[frax]

Mark - thanks for the tips/input - I also saw the resemblance with the Eckert's, from a quick visual comparison, maybe Eckert V is the closest. And you are correct that the parallells must be straight, and that the center is off Greenwich - I guess that to - but I also saw that Alaska is not broken up, which may meen so much.

Oh - and with Winkel III, I meant Winkel Tripel - apologies for the confusion.

[frax]

Don't you sometimes with there was something like "what the font" (that webservice where you can upload a graphic to get an interpretation on what font it was) for map projections? Not that "what the font" is that accurate though (I have had both hits and misses there).

I wish Tissot's indicatrix would come over and whip that graphic designer!

[Hans van der Maarel]

Don't you sometimes with there was something like "what the font" (that webservice where you can upload a graphic to get an interpretation on what font it was) for map projections? Not that "what the font" is that accurate though (I have had both hits and misses there).

Isn't that what Cartotalk is for

I wish Tissot's indicatrix would come over and whip that graphic designer!

That can be arranged of course...