Talk:Gall-Peters projection

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An example of this one would be great. I'm familiar with the Mercator projection, but can't imagine what this one would look like. --KQ 18:09 Aug 8, 2002 (PDT)

Here are some samples of various projections (copyrighted page, so we can't steal them): http://www.geog.ouc.bc.ca/physgeog/contents/2a.html --Brion VIBBER
Here one can find PDF versions of MANY projections: http://www.ilstu.edu/microcam/map_projections/index.html and it says at the bottom "Graphics as of 12/24/2004, created and released into the Public Domain by Paul B. Anderson pbander@yahoo.com (A member of the International Cartographic Association's Commission on Map Projections)" --
Oh... those. I've seen those. I don't think they'd be too hard to "reverse engineer", actually--just take a PD Mercator projection and use the GIMP or Photoshop to squash it at the top and bottom. I'd try it now except I have to pack for a trip. Anyway, thanks. --KQ 18:19 Aug 8, 2002 (PDT)
I think (and I might be wrong) that what you've suggest would not work. The Peters map is not just a stretched or squashed version of Mercator. In fact, I think you'll find it's stretched N-S at the equator (but squashed E-W there, relative;y speaking) but at the poles it's the other way around. Anyway, I don't think simple manipulation of a Mercator in GIMP will give you a real Peters, though maybe you could created something that looked a bit like one.

Where can I get data showing the outlines of the continents? With that I could code up the map projections (I have code for some stashed away somewhere, and Gall-Peters is pretty easy) and draw them. -phma

FTA: Within geography more generally, some commentators see the cartographic controversy over the Peters world map as a sign of immaturity in the cartographic profession regarding the fact that all maps are political.

Perhaps I've been drinking the koolaid for too long, but there are technical reasons for some map projects. Or perhaps it is just a coincidence that routes on a Mercator projection are a straight line!

Some commentators may think that all maps are political. I don't doubt that some commentators think that all maps are a conspiracy against flat earthers.  :D

I'm unhappy with the wording of the quoted sentence. Perhaps we need a pro/cons section of the article?

--Dasunt 23:26, 5 February 2006 (UTC)

It's impossible to eliminate an "agenda" from a map, since the map has a purpose. All maps distort. You must choose what to put on and what to leave off a map. The agenda, and the decisions that go into fulfilling it, are argued to be "political". While that may be true (depending on definitions), it would be an unfounded leap to claim that the political aspects of most map carry significance for their audience. Therefore I think rather dimly of the unjustified politicization promoted by some commentators, but I don't question the fact that all maps are (at least faintly) political.

Strebe 05:51, 10 April 2006 (UTC)

Contents

[edit] NPOV

The section entitled "the controversy" needs some serious NPOV work and should have citations. WP doesn't say things like "All of those claims were erroneous", even if such is true, without attributing the statement. -- Jonel | Speak 13:12, 8 April 2006 (UTC)

I can't find any citation to justify the claim that Peters finally acknowledged the prior art of Gall. I wonder if he really did.

Strebe 05:40, 10 April 2006 (UTC)

the 'controversy' section says, in part, "Faced with his notoriety, by 1980 many cartographers had turned overtly hostile to the problematic claims many viewed to be truculent, exaggerated, or outright erroneous." wow. there's a serious pov issue here, not to mention a prose so purple it borders on ultraviolet. anyone want to take on a rewrite? frymaster 20:16, 4 May 2006 (UTC)

Frymaster, could you describe precisely what you think is wrong with the point of view, rather than just accusing the prose of having a "serious pov issue"? The passage reports that some cartographers viewed the claims a particular way. That's completely neutral. As for your complaint about the prose color, is it the use of capital letters that blinds you, or was it just the hardly-exotic-words you don't happen to know?

Strebe 23:28, 6 May 2006 (UTC)

I agree with Jonel and Frymaster that there is a NPOV issue here, the text generally reads as pretty harsh on Peter. Tomgreeny 23:45, 18 February 2007 (UTC)
Disagree. The entry is as balanced and NPOV as can be expected from a narrow but highly controversial subject such as this one. It would be POV to downplay the controversy, particularly as the PP has been repeatedly and convincingly rubbished (strong though that may sound) in the literature (quite a bit, though by no means a large fraction, of which has been cited in the article).Brockle 10:40, 16 April 2007 (UTC)

Hi, I would like to contribute this NOPV discussion by describing how I ever found this Gall-Peters map: All my life I've seen only two maps; the round globe with a lamp inside (you know, the familiar sphere) and the mercator map in every book I've read. Everytime I saw different kind of map (For example centered on Antarctis) I couldn't relate it to these two maps. I saw the world as a Mercator even though I didn't know its name! I _knew_ that Greenland is not that big but couldn't say how much it was wrong. Then I stumbled on this Gall-Peters kind of map at wall of a hostel. I just couldn't get my eyes from it. Africa was big. Greenland small. It was totally fascinating.

I spent my time searching the map from the internet, and then found this page. It was a total disappointment. I mean, the guy who opened my eyes to the world was seen as an amateur and no-good man in this article. If this is an encyclopedia, I would like to point out that what that man did, made a difference to an ordinary man like me. I don't really care if the map is not mathematically correct or you can't sail with your ship to a another country. I mean.. Now I really understand why Africa countries are so divided. They have a desert as big as Europe!

And finally, my humble proposition to correct this NPOW issue. You could move all the dispute to the Peters' personal page, if that exists. There it wouldn't be such a big NPOW, because if you stumbled _there_ you would like to know the personal battles of that man.

62.142.198.159 10:17, 15 May 2007 (UTC)

I think that the Controversy section is simply too long and too relevant in this voice. in effect moving it, making a voice apart or make a synthesis would be more effective.
for example what Peters did or not did in relation with cartography associations should figure under his personal page and if there are a evolution in the consideration of this type of map it should be listed as this, or if there is a "Peters question" in the cartogrphists community it should be listed under its name.
80.104.141.45 13.34, 16 May 2007 (UTC)

I don't quite grasp what "too relevant in this voice" means. The Gall-Peters projection is largely defined by the controversy and its history. There probably wouldn't even be a Wikipedia entry for the projection without the controversy. Hence I'm not sure trying to move that section somewhere else would benefit the article. Peters's actions in the affair belong in the discussion of the projection and certainly within the discussion of the controversy. Don't they?

Strebe 01:09, 17 May 2007 (UTC)

See, I knew the Gall-Peters map also without knowing Peters name and absolutely not knowing this polemics history.
now it isn't that in this way the voice isn't comprehensible and maybe now I'm more informed on academic diatribes then before, but the voice is about Gall-Peters map that is a quite widely knowed kind of map, different from other Gall projections.
I'd rahter find relevant an explanation on why the rectangles on the Gall-Peters are not regular squares. wich now I don't know, but I know how this kind of map that I find on my textbooks some year ago have been welcomed 30 years ago.
80.104.141.45 11:37, 17 May 2007 (UTC)

[edit] Citation needed ?

The paragraph about the names given to the Gall-Peters projection is crisp clear and absolutely neutral. In its last period it is said that, in recent years, the designation Gall-Peters “seems to prevail” . Why is a citation needed to justify this statement? Is there any published study revealing a systematic counting of all written and spoken occurrences? If not, better to accept the fact that, in specialized literature, the name Gall-Peters is indeed prevailing. Of course, I took off the “citation needed” tag. Alvesgaspar 08:31, 12 May 2006 (UTC)

Given that Peters is a highly controversial subject and the camps for and against it highly polarised, I agree that the tenor of this article is well balanced, fair in how it represents both sides of the arguments, and as much NPOV as possible. Peters has been roundly criticized, not only by stodgy cartographers, as some of Peters's defenders would have it, but by a broad range of geographers, including many with interests or involvement in the sorts of broad social and development issues and movements alluded to in the article. Brockle 10:31, 16 April 2007 (UTC)

[edit] Individual points needed

It would be nice to have a list of the individual points the map aims to address. That is, the fact that the equator is placed in the middle, the Greenland v.s. Africa problem, North v.s. South , europe v.s. Africa and so on. Those are found on the web site and on the actual printed maps as well.

[edit] Explicit formula?

Could someone please add the function that relates a point of the Earth's surface to the point on the map under hits projection? Tompw 16:43, 20 June 2006 (UTC)

Here it is: x = cos(45)*long; y = sin(lat)/cos(45) (lat = latitude, long = longitude) Alvesgaspar 21:45, 20 June 2006 (UTC)
Looks about right, I TeXified that and put it in; also included the alternate form of cos(45) for the sake of it, it's a bit nicer-looking I think. --tiny plastic Grey Knight ⊖ 11:25, 13 February 2008 (UTC

[edit] New image

I've replaced the old line drawing with a projection of a satellite view of the Earth. The black bars on each side may be "disturbing", but it needs to be noted that this is part of a larger series of images of projections I have prepared with a common image size to ease comparisons. For example, view this article in one window and you can "blink" compare with Winkel Tripel or Goode homolosine projection and so forth in another window. Of course, if this is insufficient rationale, feel free to revert and I'll leave this article all by itself. mdf 14:40, 14 September 2006 (UTC)

[edit] Confused

"the surface area of a sphere and area of the cylinder containing it are equal." --area is a 2D concept and a cylinder is a 3D figure, I truly don't understand what this could possibly mean (& "containing it" is a very vague term)

I'm confused by your confusion. Earth's surface is a 3D object. Are you saying you don't see how the Earth's surface could have area, either? A cylinder has a surface. Any surface has area. The exterior surface of the minimal open cylinder containing a sphere has the same surface area as the sphere it contains. The text expresses the notion correctly and concisely, albeit not pedantically completely. Strebe 23:21, 20 April 2007 (UTC)

no the text says "surface area" of a sphere and "area" of a cylinder, it should say "surface area" of a cylinder but it should also define "containing it" such that the two surfaces are tangent at however many points but do not otherwise intersect, I'll fix this just felt bizarre doing it when i have no idea of the truth of the statement

... & don't patronize me 140.247.47.139 03:37, 23 April 2007 (UTC)

[edit] This is ridiculous

There is scarcely any connection between the land area of any given state and its population, political system, economy, and foreign relations. How exactly is this projection a "social justice" issue?

Really? As far as population, 3 of the 5 largest countries in the world by size are the largest in terms of population. 3 of the five smallest by area are the smallest by population. I would guess that monarchies are more likely to occur in your Monaco's and Lichtenstein's than in your Russia's and China's. Economy? I'd far sooner face an embargo from San Marino than I would with Brazil. And if you don't think the big, populous countries don't have more weight to throw around in foreign policy, you're kidding yourself. It sure seems like a "social justice" issue to me.--YbborTalk 00:18, 1 October 2007 (UTC)
Yes, really. You chose 3 of the 5 largest countries when the two largest don't suit your argument at all. There is some correlation between land area and population for the simple reason that a bigger country can hold more people. The correlation is weak, though; so weak that the largest by area doesn't even make the top 5 in population -- and you're the one who arbitrarily chose "top 5" to make your point. The second-largest hardly ranks at all. What sense does it make to demand an equal-area map to represent PEOPLE when the correlation is so low? You go on about correlations with political systems and economies, but again neither of those correlations is perfect or even strong. You're the one kidding yourself with sophistry. A perfectly equal-area map is no better than a compromise projection for "social justice" because the association between population and land area is so weak. And in any case, there are, and always have been, an unlimited number of equal-area maps to choose from.
The only reason this projection is a social issue is because a small group of loud people have adopted it as their symbol. It has nothing to do with the objective merits of the projection. Strebe 20:05, 1 October 2007 (UTC)


Absolutely not ridiculous. In the typical Mercator projection tropical cuntries are very reduced in size in comparison with sub-artic ones. Europe seems doubly large than it is while Africa or India look terribly smaller than they actually are. It's not a matter of population (that may evolve) but of real areas.
Even in a map of Europe for instance, Spain looks smaller than Sweden, when it's a lot larger. Or, again in the global map, Australia looks smaller than Greenland. That's the problem with Mercator projection or raher with the widespread use of this (otherwise useful) projection in nearly every sort of maps.
Peters projection solves this quite well.
The problem is that some "loud people" prefer to see Greenland several times its size strenagely enough. But, well, Wikipedia is not a forum. Let's stay focused. --Sugaar (talk) 03:29, 5 December 2007 (UTC)
What does Mercator have to do with anything? Everybody already agrees: we should not use the Mercator projection for general reference world maps. It's not about Mercator. It's about Peters. Perhaps YOU should stay focused. Strebe (talk) 17:33, 5 December 2007 (UTC)

[edit] Gall-Peters? Aren't both "projections" different?

According to this site (admitedly apologetic of Peters' work and ideas, but also showing clear knowledge of the issue) Peters' "construction" (sic) is not Gall's projection, even if they may have some similarities in aim.

In quotes:

The difference between the Gall's Ortographic Projection and Peters-Map is:

  • Rev. James Gall assumes the earth as a sphere and projects his grid trigonometrically with the standard-parallel of 45°.
  • For his construction Arno Peters assumes the earth as an ellipsoid and he develops his grid geometrically on the basis of area computations. The latitude of no distortion (standard-parallel) results from the method of construction and varies with the selected ellipsoid.
The world maps of Arno Peters and Rev. James Gall are very similar but they are not identical. A Peters-Map can only be such which has been designed using his method of construction. Any other map which has not been designed using Arno Peters method of construction can never be a Peters-Map.

There is more: the Peters method (not any simple projection but rather a construction) in whole detail, etc. While the results may be apparently similar, Peters' product seems to be a true equal area map, while Gall's is only an approximation.

I'd suggest that the cartographers around take an in-depth look and proceed to split (and clean up) the article accordingly. --Sugaar (talk) 03:20, 5 December 2007 (UTC)

You seem to assume, because the article you cite describes both the ellipsoid and the Peters projection, that Peters must have based his maps on ellipsoids. He didn't. His own written description of his method do not discuss development on the ellipsoid; nor is there any reason to because the difference between the spherical Gall-Peters and the ellipsoidal Gall-Peters is negligible. Gall's projection is perfectly equal-area. It is also a "construction", like almost all projections in actual use.
These distinctions you strain to find between the Peters projection and the Gall are no distinctions at all — and even if they were distinctions, the distinctions would have no meaning because they would be imperceptible. You are reading far, far more into the science of Peters's projection than Peters himself put into it. He was all about the big struggle, not struggles so tiny that you have to argue whether they even exist. I think he'd be embarrassed to have someone defending the uniqueness of his projection by resorting to splitting microscopic hairs. Strebe (talk) 18:02, 5 December 2007 (UTC)
Well, it does seem they are different methods. I know Peters never made an issue of it but in any case, it does seem that the people defending they are one, are ignorant of Peter's system.
Additionally there are several Gall projections, the one similar to Peters' being (if I'm not wrong) the stenographic one. --Sugaar (talk) 00:02, 7 December 2007 (UTC)
No, the Peters projection is the same as the Gall orthographic — read the Wikipedia article, at the very least. There is no "Gall stenographic"; there's a "Gall stereographic". There is no controversy over whether the Peters projection is the same as the Gall orthographic. It is the same. There are people who have actually studied this stuff, if you can imagine, and they are well cited in the Wikipedia entry. One of them (Snyder) was the dominant map projections expert of the 20th century. This is not a productive conversation. Strebe (talk) 20:26, 7 December 2007 (UTC)
      • Nice to meet you here, daan! Still struggling with the Peters projection? Maybe a new religion will be created soon; and then, it will be a matter of faith and no rational arguments will be allowed any more! Regards, Alvesgaspar (talk) 00:18, 8 December 2007 (UTC)


My, there seems to be plenty of heated discussion on this page - I had no idea the Peters projection was so controversial. What an interesting read! I agree that given the strong feelings displayed above, the controversy section is neither too long, nor misplaced in this article. I also feel that it could be reworded to clarify who thinks what and why. Right now it reads a bit like a specialist's argument with other specialists - so to a relative novice on the subject, it's confusing. For example, in this phrase: "Mercator's inappropriate use in world maps..." Marcato's inappropriate use of what? And why is it inappropriate? Or rather, who thinks so - Peters himself? Maybe the experts or the original author could help us out on these things. Ah, and on that note: I don't understand the relevance of the middle paragraph in the "Peters World Map" section; why does it matter if there was a discrepancy between his text and the description? [Does 'description' here mean 'image'?] Obviously it must be important to somebody, or it wouldn't be included, but from the lay-perspective it's quite confusing. Please help? Thanks! Isocephaly (talk) 00:35, 4 January 2008 (UTC)

Thanks for the comments. I agree that some of the verbiage could be simplified. You have changed the meaning in some places, so I hacked at it a bit more. Take a look at the revisions to see if you think it's improved. Strebe (talk) 20:26, 4 January 2008 (UTC)


[edit] is it Peters' or Peters's?

The Wiki article on use of an added 's' after a possessive apostrophe indicates that it should be dropped where the 's' sound makes including it difficult to sound. Now is Peters' easier to sound that Peters's? I think it is. But whoever wrote the article has committed the 'sin' of repeating Peters's so many times that I have only amended it where it first appears - and I would leave to the consensus view to decide whether to change this throughout. But to me it looks and sounds all wrong. —Preceding unsigned —Preceding unsigned comment added by 172.141.230.187 (talk) 15:29, 19 January 2008 (UTC)

And to me it looks all wrong not to add the apostrophe "s". All of the journals I have written or reviewed papers for require the added "s". The Wikipedia style guide mostly wants consistency throughout the article. I will note, however, the style guide's comment: "Most respected sources require that practically all singular nouns, including those ending with a sibilant sound, have possessive forms with an extra s after the apostrophe. Examples include the Modern Language Association, The Elements of Style, and The Economist. Such sources would demand possessive singulars like these: Senator Jones's umbrella; Mephistopheles's cat." A very few exceptions are generally agreed upon, and Peters is not one of them. Strebe (talk) 23:19, 19 January 2008 (UTC)
I will also note there is no audible way to distinguish between Peter's (the name is Peter, and he's got something) and Peters' (the name is Peters and he's got something) if you do not pronounce the second as Petersez. The English possessive comes from the archaic usage "noun + his", as in, We ogled Peters his map a long while. Contracted, that is pronounced Petersez, not Peters. Hence there is no historical justification for eliminated the added "s", either spoken or written. Strebe (talk) 23:25, 19 January 2008 (UTC)

[edit] The Real Deal

From Bob Abramms, Peters Map publisher for North America: "I interviewed Dr. Arno Peters on videotape for over 25 hours during October of 2001. I can clarify some of the misconceptions that abound in the above exchanges. (1) Peters did acknowledge the existence of the Gall projection, but he only discovered it some time after the cartographic community took him to task for allegedly plagiarizing Gall's work. Gall's work was mathematical in nature as are nearly all map projections. (2) Peters initial work to create his projection was a cumbersome, laborious hand-drawing of the world, taking each quadrant of the graticule and stretching and squeezing the landmasses to fit a rectilinear map. (3) Only after his projection generated intense controversy with his exaggerated claims, did he turn the cartographic duties over to Terry Hardaker at Oxford Cartographers in Oxford UK. (4) Oxford Cartographers then took Peters “construction” and transformed it into a map based upon mathematical formulae. I argued with Arno Peters at length attempting to get to him modify some of the exaggerated claims printed on the right side of his wall map. It was to no avail. When I discussed this with Terry Hardaker at Oxford Cartographers, even Hardaker admitted he didn’t fully understand or agree with Peters claims. But Peters was a bit stubborn, and he refused to modify the map surround text to accommodate either Hardaker or myself. I recognized from a very early point that Peters’ overblown assertions were hurting the credibility of the map. Only after Arno Peters death was I able to revise the map text to make it more accurate. I believe it currently is cartographically accurate and entirely defensible. My documentary film, based on the Peters interviews in Bremen Germany, is now complete, and it available from AMAZON for $89 (http://www.amazon.com/Arno-Peters-Radical-Map-Remarkable/dp/B0014WJ4NC). Arno Peters: Radical Map, Remarkable Man is also available from ODT (http://odtmaps.com/detail.asp_Q_product_id_E_apeters-dvd) Or a trailer can be seen on YouTube (http://www.youtube.com/watch?v=osQN7aSQV9w). Anyone wishing a free copy of the DVD need only host a public screening for which no fee is charged. Sign up for a screening at http://arnopeters.bravenewtheaters.com/. Bob Abramms www.ODTmaps.com 413-549-1293

˜˜˜˜Denis Wood

Denis, now that ODT's DVD is published I added a citation. But I don't see that the DVD narrative contradicts the Wikipedia text as it stands or demonstrates any "misconceptions" or even adds anything relevant. Of course you or Bob Abramms or anyone else is free to edit as you see fit. Strebe (talk) 05:53, 11 June 2008 (UTC)


It seems Peters rediscovered the cyclindrical equal area map and the notion of standard parallels. The standard parallels make it eurocentric (ironically) but they also make it a viable map. The standard cylindrical equal area turns Europe into a roadkill. I don't see why anyone should try to insist that cylindrical maps should not be used for the world. Sure it has bad distortion but that is unformly oriented- unlike Mollweide-type that bend continents in a funny way-usually Australia suffers worst.

Jay Jackson