The projection problem of map making

1. A square peg in a round hole-
The map projection problem

2. What is a map?
• Representation
• Association
• Simple orientation
• What is a map in geography?
 Straight lines for latitude and longitude
 Correct surface area for countries
 Correct distances between places
 Correct shapes (orthomorphism)
 Constant scale

3. What is the map of the Earth?

4. And then what are these?

5. “Far
East”
“Western
world”
And then what are these?

6. And then what are these?

7. And then what are these?

8. And then what are these?

9. The problem of world maps
• A sphere or an ellipsoid like Earth cannot be accurately modelled in a
2D plane ( an empty ball cannot be flattened without deformations)
• The surface of a sphere does not have a center.
• Mercator projection
1. Line of constant direction straight
2. Retains shapes
3. Distances are more or less accurate near the equator
4. Meridians and latitudinal lines are orthogonal
…. So it used to be useful to navigators.

10. Other solutions: Gall-Peters projection

11. Other solutions: Winkel tripel projection

12. Other solutions: Dymaxion map

13. Other solutions: Autagraph map

14. In the end…
• There are no right or wrong
projections, only better or
worse maps for a given job.
• For navigation, there are
several options

15. Thank you!