Map projections [spring semester]

Time, place

Tuesday 10:15 am - 11:45 am; É7.87 (Drawing room)

Thematic

In this course we learn the mathematical base of non-conical map projections.

Suggested reading Lecture notes, http://www.progonos.com/furuti/MapProj/Normal/TOC/cartTOC.html and http://mercator.elte.hu/~saman/edu/proj/

11 Feb Introduction to non-conical maps
18 Feb Globular maps
25 Feb Blended map projections
4 Mar Auxiliary angles in equal-area maps
11 Mar Graticule renumbering
18 Mar Compound map projections
25 Mar Pseudoconic and pseudoazimuthal projections
1 Apr Polyconic projections in strict sense
8 Apr Polyconic projections in broad sense
15 Apr Modified azimuthal projections
29 Apr Conformal and polyhedral projections
6 May Selecting a map projection

Expectations

The exam is subject to the completion of a homework assignment: scan five hemispheral or global maps (>10 000 km extent) in the map library to a file with lossless compression. The maps should be from at least three different atlases. There must be at least one map whose projection you consider inappropriate (e.g. it is not appropriate for this topic or it is outrageously distorted). Upload the images to the K:\ drive and write in a text file for each map what you think its projection is, whether you agree with the choice of map projection and why (about 10-30 words per map.) If you disagree, suggest another projection!

Task 2: Talk about the theoryTask 3: Talk about the map projectionsTask 4: Derive the formula of the projection
1.Classification of non-conical projectionsMap projections based on transverse azimuthal projectionsWinkel III projection
2.Detecting the projection of a map with an unknown gridPseudopolyconic projectionsLagrange projection
3.Decreasing distortions with distortion criteriaRectangular and equal-area polyconicsWar Office projection (sphere)
4.Decrasing distortions manually (Baranyi, Robinson, Flex Projector etc.)American polyconicAmerican polyconic (sphere)
5.Conformal mappings as complex functionsPseudoconic projectionsBonne projection (sphere)
6.Decreasing distortions by rotating the graticule (7 aspects)Non-conical projections in rotated aspectsHammer projection (normal aspect)
7.Needs for special distortions (e.g. retroazimuthal, loximuthal)Pseudoazimuthal projectionsLoximuthal projection
8.Comparison of conical and non-conical projections (look, distortions)Blended projectionsEckert V projections
9.Guidelines of selecting a map projectionWagner projections, Kavrayskiy VII projectionKavrayskiy VI projection
10.Decreasing distortions visually with curved surfacesEqual-area projections developed using an auxiliary latitudeMollweide projection
11.Decreasing distortions using interruptions or polyhedraGlobular projectionsApian II projection
12.Lichtenstern projection and its approximationGoode and Érdi-Krausz projectionsSinusoidal projection (sphere)

Procedure for the oral exam: students are free to decide the order among themselves. The next victim should wait at the front of the room, so that I do not have to dig him from the other end of the corridor! (If there are four students before you, feel free to leave for the buffet.) The student rolls a dice to choose a row. The student may request a new roll to replace the task at the cost of –5 points penalty for each new roll. The task can be drafted during the previous student's answer (you can only use a pen, I will provide paper), and then you can present it in about 10 minutes, after which I will ask questions. In your answer, you may complete the tasks in any order and combine them as you wish. The fourth task is to derive a map projection or a basic formula. The constants of the conic projections do not need to be expressed in terms of the standard parallels. You should at least be able to recall the steps of the derivation! Don't try to skip it, it scores lots of points!

Grading

Task 1 (assignment): 0.5 point is awarded for each map for the correct identification of the map projection. An additional 0.5 point is awarded for the reasoning whether the projection is appropriate or not. If the map chosen does not correspond to the requirements of the specification, but the answer is otherwise assessable, a penalty of –0.5 point per map is applied. A total of 5 points can be scored.

Task 2 (theory): Explanation of basic concepts and relationships: 2 points. Correct use of terminology, definitions: 1 point. Examples of the application of the methods or classification described: 2 points.

Task 3 (present a projection): Classification of the map projections to be presented: 1 point. Examples of the proper application of the projection presented (area of interest, theme): 2 points. Describing the parameters of the projection (e.g. two equidistant parallels can be chosen) or indicating that the projection cannot be parameterized: 1 point. Historical context (name of inventor, approximate date of invention accurate to the century): 1 point.

Task 4 (derivation): “Professor, I can't do this”: 0 points + the professor will be very grumpy (not recommended for any student). If you manage to derive with help: 3–4 points depending on the amount of help. If you can do it on your own: 5 points.

Classification of map projections: it is essential that the student knows for each projection which class it belongs to according to the graticule, distortions, geometrical construction and aspect. If the student is wrong in this at any time during the exam, or if there is a mistake in the assignment, then: no penalty for the first two mistakes, three mistakes –3 points, four mistakes –8 points, five mistakes –20 points.

Grading: 7 points and below fail (1), 9–10 points pass (2), 12–13 points fair (3), 15–16 points good (4), 18 points and above excellent (5). A student between two grades will be given three quick questions from one of the other rows, receiving the better grade for at least two correct answers and the lower grade otherwise.