The Landgate barcode staff calibration range is located at the Land Surveyors Licensing Board's examination site at Boya and consists of 2 observing pillars and a series of 21 stainless steel pins set in a solid granite outcrop. The pins have been placed at optimum distances from the pillars and cater for testing over a 4 metre height difference. The relative height differences between the pins have been accurately determined by repeat observations using precision levels in conjunction with calibrated invar staves. Landgate regularly monitor and re-measure the test range to ensure its ongoing accuracy.

Landgate's Service

The Boya Barcode Staff Calibration Range is monitored on a regular basis. Landgate provides this staff calibration data processing service to ensure staves are calibrated based on a time-dependent calibration range. Please go through the following documents before commencing the field procedure:

How to calibrate barcode staves

  1. Use the barcode staff booking sheet to record the collimation details and range observations details in the field.
  2. Check the bubble of the digital level and the staff. Re-adjust them if necessary. The staff needs to be truly vertical for the best results.
  3. Perform a collimation test on the digital level and use its software to compute and store the constants calculated. For this purpose, four co-linear spikes in concrete 20 m apart have been established adjacent to the range (see the Access Sketch)
  4. Configure the settings in the digital level to record mean and standard deviation of measurement from multiple readings (at least five), if possible. Otherwise, if the instrument does not allow means from multiple observations, a minimum of three complete sets of observations (see 8 – 10 below) is required for redundancy
  5. Set the digital level on the high observing pillar (MV 83) and shade it from the sun. Pillar B (low pillar) is utilised by Landgate when calibrating the range.
  6. Position staff on the highest pin (Pin No 1) and allow at least 5 minutes to settle and adjust to the ambient air temperature. Record the air temperature in the booking sheet with a shaded thermometer.
  7. A set of observations for a standard four metre staff consist of:
    • Set up on Pillar MV 83
      • backsight to the staff at Pin Number 1
      • intermediate sights to the staff at Pin Numbers 2 to 20
      • foresight to the staff at Pin Number 21
  8. A set of observations for a standard three metre staff consist of:
    • Setup on Pillar MV83
      • backsight to the staff at Pin Number 1
      • intermediate sights to the staff at Pin Numbers 2 to 14
      • foresight to the staff at Pin Number 15
    • Setup on Pillar B
      • backsight to the staff at Pin Number 7
      • intermediate sights to the staff at Pin Numbers 8 to 20
      • foresight to the staff at Pin Number 21
  9. Record the air temperature in the booking sheet at the end of each survey.
  10. Download the level data and create a csv file in the correct format (see below).
  11. Click here to process your staff readings and print the pdf report.

Sample data to be uploaded

Data should be uploaded in a correctly formatted text or csv file as per the file format. File Format - All fields are separated by a comma and must have a header line

  • Field 1 = Pin number
  • Field 2 = Staff reading
  • Field 3 = Number of readings
  • Field 4 = Standard deviations

Example of a text/csv file. The file can also be downloaded from here.

Pin number, Staff reading, Number of readings, Standard deviations
1,0.07417,10,0.000090
2,0.16503,10,0.000070
3,0.32868,10,0.000020
4,0.47489,10,0.000090
5,0.68799,10,0.000070
6,0.87413,10,0.000040
9,1.52628,10,0.000030
7,1.07422,10,0.000030
8,1.27955,10,0.000050
10,1.79376,10,0.000040
11,2.12703,10,0.000080
12,2.3912,10,0.000050
13,2.51647,10,0.000110
14,2.64608,10,0.000050
15,2.87513,10,0.000120
16,3.05758,10,0.000060
17,3.20978,10,0.000040
18,3.36207,10,0.000120
19,3.52057,10,0.000200
20,3.6692,10,0.000070
21,3.87885,10,0.000100

Other information required are the staff and observation metadata which is recorded in the booking sheet at the time of observation. Retain a copy of the field booking sheet at least until a new calibration is done for the staff