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Abstract

The author describes the properties and mechanisms of visual perception in the context of their significance to the principles of symbol design as used in cartography. Map perception relies on the process of visual perception. Therefore, the knowledge of its inner workings in the map environment allows cartographers to construct cartographic symbols in agreement with the properties of the visual system.

Visual perception involves neurosensory processes taking place between the eye and the short-term memory. As such, they operate independently of the beholder’s consciousness and significantly influence the information received by the map user. The author discusses the mechanisms of human vision and the nature of the process of visual perception. It also shows the relationships between the image characteristic and the visual system’s properties such as the optical resolution, visual adaptation, reactions of inhibition and reinforcement, reactions to the image characteristics – as well as the phenomena of contrast, grouping and spatial arrangement.

The principles of constructing map symbols that have been developed in the long course of cartography, and based mostly on the map makers’ intuition, find validation in the light of properties and mechanisms of visual perception. As discussed in the paper, the fundamental properties and basic mechanisms of human vision support the view that knowledge of how the visual system works provides foundation for articulating new mapping guidelines and cartographers’ calls for stricter observance of cartographic principles are fully justified.

Abstract

The author discuss effectiveness of cartographic presentations. The article includes opinions of cartographers regarding effectiveness, readability and efficiency of a map. It reminds the principles of map graphic design in order to verify them using examples of small-scale thematic maps.

The following questions have been asked: Is the map effective? Why is the map effective? How do cartographic presentation methods affect effectiveness of the cartographic message? What else can influence effectiveness of a map?

Each graphic presentation should be effective, as its purpose is to complete written word, draw the recipients’ attention, make text more readable, expose the most important information. Such a significant role of graphics results in the fact that graphic presentations (maps, diagrams) require proper preparation.

Users need to have a chance to understand the graphics language in order to draw correct conclusions about the presented phenomenon. Graphics should demonstrate the most important elements, some tendencies, and directions of changes. It should generalize and present a given subject from a slightly different perspective.

There are numerous examples of well-edited and poorly edited small-scale thematic maps. They include maps, which are impossible to interpret correctly. They are burdened with methodological defects and they cannot fulfill their task.

Cartography practice indicates that the principles related to graphic design of cartographic presentation are frequently omitted during the process of developing small-scale thematic maps used – among others – in the press and on the Internet. The purpose of such presentations is to quickly interpret them. On such maps editors’ problems with the selection of an appropriate symbol and graphic variable (fig. 1A, 9B) are visible. Sometimes they use symbols which are not sufficiently distinguishable nor demonstrative (fig. 11), it does not increase their readability. Sometime authors try too hard to reflect presented phenomenon and therefore the map becomes more difficult to interpret (fig. 4A,B). The lack of graphic sense resulting in the lack of graphic balance and aesthetics constitutes a weak point of numerous cartographic presentations (fig. 13).

Effectiveness of cartographic presentations consists of knowledge and skills of the map editor, as well as the recipients’ perception capabilities and their readiness to read and interpret maps. The qualifications of the map editor should include methodological qualifications supported by the knowledge of the principles for cartographic symbol design, as well as relevant technical qualifications, which allow to properly use the tools to edit a map. Maps facilitate the understanding of texts they accompany and they present relationships between phenomenon better than texts, appealing to the senses.

the viewpoint of a graphic form and visual graphic variables, including shape and size of cartographic symbols, colours and patterns, areal units, etc. To answer this question we must acknowledge that actually the objective methods of car- tographic presentation remain unknown. Thus, if we analyze contents of a large-scale geographical map, that is as a distribution of various objects, what we see is chiefly a consciously simplified representation of a certain geographical reality. By the way, it is well known that despite an evident miniaturing of

primary plane of reading, while the remaining ones should have a lower optical weight, corresponding to the lower rank of the content. The visual order on the map, reflecting the harmony of form and substance, can be achieved by means of a skilful application of graphic variables. Our considerations so far have aimed to show how significant role in the communication of cartographic information is played by the map's graphical aspect. Naturally, it is rather difficult to question the view that map is information, but it should be stressed that there is more to the

designing the map the authors used quantitative methods: the dot method (population distribution map), choropleth (population density map), and the proportional symbol map (population change map). Qualitative methods were also used: the symbol method, the range method (map of nature conservation), and the chorochromatic method (land cover map) ( Ratajski 1989 ). The next step in the visualization was the use of appropriate graphical variables for the phenomena presented by each map. Using the relevant graphical variables helps users to perceive the image, and helps

) and their size (adjusted to map content). At this moment, the data should be adjusted to the presentation, as it may require an appropriate transformation – in other words, a change of one of the listed presentation features. Having adjusted the data to the requirements of the presentation methods, it is time for them to be visualized. The graphic sign (point, linear or plane) applied on the map is important, as well as the features or attributes of the sign, which are expressed through graphic variables. A METHOD can in fact be treated as a mental process as a

involves changes in the level of data generalisation ( Tanaka & Ichikawa 1988 ). The differences in usability of non-interactive and interactive maps is one of a prevailing research questions in cartography ( Roth et al. 2017 ). The comparison may state a challenge, because of the differences between them (e.g. medium, graphic variables). An even greater obstacle may be presented by the difficulty in comparing experiment results, as an interactive map may enable automatic measurements of length and area, filtration and selection of data. These functions substitute skills