Cartography – 2

What is good map?

-          Accurate

-          Up to date

-          Only relevant information

-          Standard symbolistion

-          Clear and legible

-          Communicate its message

-          Designed for the purpose

Type of maps

-          Topographic maps

Topographic maps are replacing general image of the earth’s surface such as roads, river, vegetation, etc.  

-          Thematic maps

Thematic maps are focuses on particular phenomenon or subject area. This them or subject can be political map, rainfall in an area. Thematic maps divided in to three map category;

Choropleth map – choropleth map uses to demarked differences in shading, color or the placing of symbols variable being displayed on the map, such as population density.

            Isopleth map - continuous surface maps, like topographic contours.

            Area class map- Showing zones like, vegetation, soil type.

Map Scale

Map scale is one of the most significant elements on a map. Map scale is the ratio between map distance and corresponding ground distance in real world. There are three methods of map scaling;

-          Statement of scale

Ex. 1 centimeter to 6 kilometers

-          Representative Fraction (R.F)

Distance expressed in the same unit of measurement, 1:25000

-          Linear Scale (Graphic or Bar Scale )

It is graphic scale, plain scale or bar scale.

Representative Fraction

It is always written with the map distance taken as 1 unit. This unit measurement can be any unit(ie Centimeters, inches, feet) The R.F of 1:50000 means that one unit of the map equal to 50000 units in the real ground.  

Ie. Two point of the map A to B is 6 cm and the real ground distance is 3 km. fiend out map scale.

  Map Distance           6cm/3km        

Ground distance

          6cm      

3 x 100000cm

1: 50,000

Map Title

Title should be reference to map, it should included “ What, Where, How and When.