Summary of Map Semiotics
Visual Variables according to Jacques Bertin
Bertin Who?
Jacques Bertin French Cartographer and Semiologist Develops a theory of cartographic communication based on the interaction of 6 visual vaiables This theory forms still important “Semiology of Graphics” is his landmark work on this subject
Semiology
The study of signs and ciphers Critical importance to cartographers Signs and symbols have different levels of meaning and interactions Map as discourse - not just a collection of symbols telling us about a single area but a ongoing discussion
Semiology II
One way to understand the implications of map semiology of Bertin is to compare it to other well known works. Marshall Mcluhan sorts well with Bertin The “medium is the message” Important advice for the cartographer
Bertin’s 6 Primary Visual Variables
Points to remember
There is always a logic to the usage of the visual variables Variables are on ascending scales of complexity/intensity The variables are complimentary to each other, the theme of the map, and the ongoing discourse
Point Symbols
Pointers about Points
Once again the logic each type has a unique function Note effectiveness of the pictorial icons, spare the viewer multiple references to legend if used correctly Note the relationship of linear, areal, and volume scaling
Point Symbols II
Line Symbols
Line pointers
Logic logic logic Ascending scales of intensity and complexity Flexibility: how fine a line can one use Final output feeds back on production process in this regard Consider the relationship between linear scaling and potential effect on flowing lines
Attenuating and Flowing Lines
Blurring the line
Attenuation combines point and line properties We might be tempted to use more advance transparency/opacity operations to achieve similar effects But these are inoperative in reduced resolution and line art end environments
Loose Lines
Orientation is not generally thought of as a linear attribute, more often associated with polygons and points Flow lines, and isolines however do use orientation to convey meaning each in very different ways
Ambiguity and Clarity: visual logic using point and line
The Logic of Shading
The example shows how point and line, organized as a Shade/fill follow the same hierarchical logic Ascending/ descending hierarchies of complexity and intensity to form complimentry/synchronized visual messages.
Summary
The central message of Bertin is that there is a logic of visual communication He always shows that the ascending/ descending orders of point and line in concert with the six visual variables are not only logical hierarchies of cartographic expression but are also aggregates of visual meaning adding subtle yet powerful messages pertaining to the discourse that surrounds and binds the map together