摘要：Map projections and coordinate transformations are the basis of achieving a common frame of reference for geographic information. The requirement of a common ellipsoid, datum, map projection, and finally plane coordinate systems make it possible to use plane geometry for all types of spatial overlay and analysis. Projection of geographic data from the ellipsoidal Earth to a plane coordinate system always results in distortion in area, shape, distance, and other properties. With appropriate selection of a projection, the user can preserve desired characteristics at the expense of others. For the production of Albanian maps are used different cartographic projections. This is explained with the fact that most of these maps are created from foreign persons and geographic institutions, keeping safe their cartographic traditions. The cartographic projections used as mathematical base of topographic and thematic maps of Albania are: Polar conic projection in the new edition of Ptolemy maps; Gauss-Krüger projection in Bessel ellipsoid, with origin the intersection of the Equator by the meridian of Ferro with λFerros = 17° 39’ 46.5’’ in the maps, scale 1:75000 and 1:50000, published by Military Geographic Institute of Wien (1868-98, 1913-18); Polyconic equivalent Projection of Bonn in Clark ellipsoid with origin the intersection of the Equator by the central meridian Λ0 = 180 39’ 09‖, in the maps of scales 1:50000, published by Military Geographic Institute of Florence (MGIF) (1922-25); Bonne pseudo-conic equivalent projection in Bessel ellipsoid with origin the intersection of parallel Φ0 = 41° 20’ 12’’.809 by the central meridian Λ0 = 19° 45’ 45‖.285, in the maps of scales 1:50000, published by Military Geographic Institute of Florence (MGIF), Italy (1927-1934); Gauss ‐ Boaga projection in Bessel ellipsoid with origin the intersection of the Equator by the central meridian Λ0 = 200, in the maps of scales greater than 1:50000 and topographical plans of residential areas at 1:5000 scale, published by Military Geographic Institute of Florence (MGIF) (1939 - 1948); Gauss-Krüger projection in Krassowsky ellipsoid with origin the intersection of the Equator by the central meridian L0=21º in the maps, scale 1:25000 and 1:10000, published by Military Geographic Institute of Albania (1950 - 1955, 1970 - 1992)4. During the period 1946-1996 are also created a series of cadastral maps (which covered approximately 56.27% of the Albania’s territory) in scale 1: 500; 1: 1000; 1: 2000; 1: 5000; 1: 10000 and 1: 50000. Cadastral maps created during the years 1946 - 1960, are in 1: 2500 and 1: 5000 scale and based on the Bessel ellipsoid, Gauss-Kruger projection and the central meridian Lo = 20º 00'. Almost all cadastral maps created after 1960 were constructed in the state coordinate system: the Krasowsky ellipsoid, GaussKruger projection and central meridian Lo = 210 00’. UTM projection in WGS 84 ellipsoid with origin the intersection of the Equator by the central meridian Λ0 = 210, in the maps of scales 1:50000 and 1:25000, published by Military Geographic Institute of Albania (MGIA) (after 1994); Version of the pseudoconic projection, developed by prof. dr. Agim Shehu (Polytechnic University of Tirana, Albania) in the Earth sphere, was used for the first time at the ―The geographical atlas of Albania‖ 1968, in the scales 1:2000000 and smaller ones. In the 1980 year this projection was used for the creation of the maps of Albania in the scale 1:200000, as geological, hidrogeological and fitogeographical maps, etc. also it is used for all (127) the maps of ―Climatic atlas of Albania‖, 1986, in the scale 1:800000 and for all (256) the maps of ―Agricultural geographical atlas of Tirana district‖ in the scales 1:100000.
