Question

Height of collimation method is ______ and ______ labour is required as compared to Rise and fall method.
1. rapid, more
2. rapid, less
3. slow, less
4. slow, more

Answer 1

Correct Answer - Option 2 : rapid, less

Rise and Fall Method:

• It is adopted whenever the number of intermediate stations is more and also if the number of shifting of instruments is more
• The difference between the levels of consecutive staff points is calculated
• The rise and fall method for obtaining the reduced levels of points provides a check on foresight, backlight & intermediate sight.
• Generally used for fly leveling, profile leveling or to establish BMs
• ∑BS - ∑FS = Last R.L – First R.L = ∑Rise - ∑Fall​

 

Collimation Method:

• This method is generally adopted if there are lot many numbers of intermediate stations and also if the number of shifting of instruments is less
• It does not provide a check on Intermediate sights
• Height of instrument is calculated at each set up of the instruments
• Generally used in contour survey, in small areas
• Checks: ∑BS - ∑FS = Last R.L – First R.L