for those interested in GIS field

1. Geographic Coordinate System & Map Projection By- VishalKedia M.Tech(Remote Sensing & GIS) Maulana Azad National Institute Of Technology BHOPAL

3. Surface of Geoid matches very much with the MSL.

4. Mathematically earth is represented as spheroid.

5. Spheroid is the three dimensional structure formed by the rotation of an ellipse about the minor axis.

6. For the purpose of obtaining R.L. of any point on earth surface Geoid approximation of earth is assumed.

7. For the purpose of obtaining geographic coordinate of earth pure spheroid or ellipsoid is assumed.Our earth…(some facts)

8. Geoid Undulation: separation between geoid & spheroid at any point on the surface of the earth. Geoid undulation Vertical deflection

9. What is Datum?

10. Geodetic Datum:

11. Vertical Datum:

12. Different Ellipsoid Models

13. Example Datum:

14. WGS 84 – Parameters:

15. WGS 84 – Parameters(cont.)

16. Geographic Coordinate System

17. Lattitude & Longitude

18. Lattitude & Longitude(cont.)

19. Projection ?

20. Projection(cont.)

21. Projection(cont.)

22. Projection(cont.)

23. Projection(cont.)

24. Projection(cont.)

25. Rectangular coordinate system

26. coordinate system and map projection

27. Utm coordinate system

28. Utm coordinate system(Cont.) It is the modified form of Transverse Mercator Projection System in which instead of using one cylinder as developable surface we use multiple cylinders that touch the globe at 6 degree interval meridians resulting in 60 projection zones each of 6 degree longitude width. To avoid extreme distortions projection zones are limited to 84 N & 80 S.

29. Utm coordinate system(Cont.) UTM coordinate system is formed by superimposing a regular grid on each projection zone such that vertical lines are parallel to the central meridian. Each UTM zone is divided into horizontal bands spanning 8 degrees of lattitude & these are identified by the letters North to South beginning at 80 S with letter ‘c’ and ending at 84 N with letter ‘X’ , letter ‘I’ & ‘O’ are not used (skipped). Band ‘X’ spans 12 degrees of lattitude.

30. Utm coordinate system(Cont.)

31. Utm coordinate system(Cont.) UTM coordinates are expressed as a distance in meters to east – ‘Easting’ & to north – ‘Northing’. UTM easting of central meridian is 500,000 m east ie. false origin is 500,000 m west of the central meridian.

32. Utm coordinate system(Cont.) Equator is assigned 0 m N (zero northing). To avoid –venos for locations south of the equator position fixing in the southern hemisphere is made with equator assigned a value of 10,000,000 m S. By combining the zone no, the hemisphere, easting and northing values; each point on the earth surface can be uniquely located.

33. Any questions?

34. Thanking you!