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I was reading an article that said when we display a map in WGS84 many people call it no projection. But most definitely when you see the map it has been distorted on a 2D surface.

Which got me to thinking is there such a thing as a "map" with no projection. If I'm looking at a 3D digital globe it is representing how it would look as if I were out in space. So then it wouldn't be projected. But if I'm looking at the globe on a screen then it is being rendered on a 2D screen so it is projected.

Is there such a thing as no projection?

PolyGeo
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sinDizzy
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    The term 'no projection' means that the data is not projected but in geographic coordinates.. coordinate systems are of two basic classes projected and geographic, thus anything representing a map in geographic coordinates can be said to be 'Unprojected'. The reason you don't see maps in unprojected coordinates very much is they're not all that useful, you can't measure a distance or take a bearing very well in geographic coordinates however you can show the general relationship between two landmasses great distances apart. – Michael Stimson Feb 15 '18 at 02:29
  • But in ArcMap when I generate a map and set it's spatial reference to WGS84 the resulting land masses are distorted. Isn't that the very basis for projection? From several sources "A map projection is a systematic transformation of the latitudes and longitudes of locations from the surface of a sphere or an ellipsoid into locations on a plane. Maps cannot be created without map projections." So maybe it's a misnomer but setting the map to a geographic spatial reference definitely maps it on to a 2D plane. – sinDizzy Feb 15 '18 at 02:44
  • That is half my question. The second part is asking about a globe like Google Earth or ArcGlobe. – sinDizzy Feb 15 '18 at 03:32
  • As per the [tour] there should be only one question asked per question. If one has been answered and you have another then you could either ask a new question about just the second part, or because it has no answers, you could edit this one to make it only about the second part. – PolyGeo Feb 15 '18 at 03:36
  • I see. Looking back the first part is an intro and the second part is my question. I guess I do t get why it was closed. – sinDizzy Feb 15 '18 at 03:46
  • Perhaps review https://gis.meta.stackexchange.com/questions/3349/asking-good-questions-for-gis-stack-exchange – PolyGeo Feb 15 '18 at 03:47
  • So how would I be able to re-ask that? I needed to make a statement about no projection on a map and then follow it up with that idea but instead about a globe. – sinDizzy Feb 15 '18 at 03:50
  • It is your question so perhaps re-read it a few times to see if you can make what you want to ask clearer. The only marked question makes no mention of a globe being relevant to it. You also provide no link to the article mentioned at the beginning, or reference to understanding the connection between WGS84 and Plate Carree for 2D, which is described in the duplicate. To me the statement about a globe/3D seemed like an afterthought to asking about a map/2D. – PolyGeo Feb 15 '18 at 03:56
  • Got it. Last question(s). Do I delete this post? Can I delete it? Do I just make a whole new post for the revised question? – sinDizzy Feb 15 '18 at 04:07
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    You can delete it (because it has no answers) but I always think that a question with no answers is ideally suited to be heavily revised by using the [edit] button. To get it reassessed for re-opening after editing either leave it to the review queue or ping me using @PolyGeo – PolyGeo Feb 15 '18 at 05:05

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