Mapping the Universe - Mapping Scientific Frontiers: The Quest for Knowledge Visualization - page 53

Fig. 2.4 Four types of relief map: ( a ) contours, ( b ) contours with hill shading, ( c ) layer tints, and
( d ) digits (Reprinted from http://www.nottingham.ac.uk/education/maps/relief.html#r5 )

2.1.2 Relief Maps and Photographic Cartography

Relief maps are used to represent a three-dimensional surface, such as hills, valleys
and other features of a place. Techniques such as contour lines, shading, and
layer tints are commonly used in relief maps. Reasoning in three dimensions
requires skills. Many people find relief features harder to interpret than most other
information on a map. There are more than a dozen distinct methods for showing
relief and so the map designer has a wide choice (See Fig. 2.4 ).
Information visualization has adapted many techniques from relief maps to
represent abstract structures and volatile phenomena. Notable examples include
self-organized maps (SOMs) (Lin 1997 ) and ThemeScape models (Wise et al.
1995 ). See Chap. 4 for more details.
In Chap . 1 , we introduce the view of visualism of science, which emphasizes the
instrumentational role of technologies in scientific discovery. Earlier cartography
relied on craftsmen's measuring and drawing skills. Today, photographic cartogra-
phy relies on new technologies. For example, the powerful Hubble Space Telescope
(HST) took high-quality photographs of stars and galaxies for celestial mapping.