1. Stadia Reduction

2. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.

3. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
The middle line is used for levelling

4. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
The other 2 lines are stadia lines

5. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
Stadia lines are used to measure distances.

6. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
Note – These measured distances are not intended to be used for setting out.
They should be used for measurement for detail surveys.
Stadia lines are used to measure distances.

7. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
Top 3.040

8. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
Top 3.040
Bottom 2.947

9. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
Top 3.040
Bottom 2.947

10. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
Top 3.040
Middle 2.993
Bottom 2.947

11. Stadia Reduction
When you sight the through the telescope on most instruments you will see 3 horizontal lines.
Top 3.040
Difference Top & Bottom = 0.093
Check
Difference Top & Middle = 0.047
Difference Middle & Bottom = 0.046
Add difference = 0.094
Middle 2.993
Bottom 2.947

12. Stadia Reduction
Most instruments have a stadia constant of 100, you should check the documentation.
Top 3.040
Difference = 0.093
Bottom 2.947

13. Stadia Reduction
Most instruments have a stadia constant of 100, you should check the documentation.
Top 3.040
Distance = x Stadia Constant
Distance = x 100
= 9.400m
Bottom 2.947

14. Stadia Reduction
Top __________
Middle _______
Bottom _______

15. Stadia Reduction
Top
Middle
Bottom 1.871

16. Put Stadia to Work Set up the instrument
Measure the position in relation to known features

17. Put Stadia to Work Set a zero point for the horizontal circle
e.g. measure horizontal distance to boundary

18. Take back sight as normal & book readings

19. Putting Stadia to work

20. Putting Stadia to work

21. Putting Stadia to work

22. Putting Stadia to work

23. Stadia
Determine reduced levels of your spot heights

24. Stadia
Draw to scale site plan & instrument position

25. Stadia
Draw in Azimuth

26. Stadia
Draw in Observations

27. Stadia
Draw in Observations

28. Stadia
Draw in Observations

29. Stadia
Draw in Observations