Precision Stadia
This tutorial / white paper explains the improvements we have been doing to the stadia entry, and adjustment routines. The following improvements have been achieved
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The stadia now accepts decimal seconds. At present this is hardwired to display to the 1 hundredth of a seconds
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We have added in an optional vertical refraction coefficient. Leave this value at 0 for no correction. A value of 14 is recommended ( metric only)
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We have added in the appropriate corrections to a Geoid if wanted. If this option is ticked the appropriate correction is applied. At present we have MGA, and ISG predefined as well as a Custom option for other geoids.
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Least squares network adjustment has also been added in
Displaying precision stadia
The precision stadia type is a new type which is included as well as the “Electronic Stadia” type that has been included for the last 18 years plus. Unless you need the geoid corrections or a least squares adjustment we suggest that you continue to use the existing version.
From the entry menu you will see the new option precision stadia. Simply click on it. Select new or existing as you always have. If you only have an existing “Electronic Stadia” file then this can be brought up as well. Click on the browse button and select a file type as stad – . The program will open up the existing stadia as a precision stadia display. On saving the file a new precision stadia file is created. The existing stadia file is not affected.
Opening supplied data
If you point your web browser to ftp.foresoft.com then you can download and save the file geoid_stad_example.cab into your appropriate data directory. Open up CDS and select options. Select the “Restore data” item and browse to the geoid_stad_example.cab file. Restore this data.
From the file menu select “open” and browse to the saved file. Select the “db.geoid_stad_example” file and a blank job will open. To bring up the new precision stadia file select “Entry” and then “Precision Stadia”. The following screen will be displayed.
The observant ones will notice the new tool bar. The following functions have been added or shown on the toolbar.
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The calculator icon recalculates the coordinates
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The tick box “Geoid Correction”. Tick this if you want the calculated coordinates to be corrected to the appropriately define Geoid. For eg MGA, ISG or whichever you select.
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Geoid parameters. Click on the circle (actually a flattened version of the Earth ) to bring up a dialog box were you can either select a predefined Geoid, eg MGA or enter your own values. The dialog box is shown opposite
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Vertical refraction value. Leave at 0 for no correction.
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Least squares adjustment. Click on the two box's icon.
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The data supplied is MGA so make sure that the MGA geodetic values are selected. To check on the operation of these corrections I suggest that you open up the precision stadia as described above. For our first calc's we are going to assume it is a plane and there is no vertical refraction coefficient specified. Click on the calculate icon and display the Eastings, Northings and Height displayed. As a quick check I suggest that you note the coordinates of the check-shot back to Stn 2 as a comparison with the defined values. Next i suggest that you enter a value of 14 for the vertical refraction coefficient and calculate again. Next I suggest that you tick the Geoid selection tick box. First make sure though that the Geoid parameters are for MGA. Each calculated value should be closed to the reference value. I have summarized the results below:
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East
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North
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Height
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Stn Coordinates
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347166.813
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6361107.535
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99.169
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Plane calculations
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347166.819
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6361107.509
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99.158
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Plane + vertical refraction
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347166.819
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6361107.509
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99.162
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Geoid + vertical refraction
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347166.812
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6361107.538
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99.162
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By inspection we can see that we are heading in the right direction.
Least Squares
Pressing the Least Squares Icon will run Least Squares on the network. First fill in the appropriate values for “distance accuracy” in mm's, “Parts per Million” typically 3 or 5 and “angle accuracy” in secs. Simply press the Continue button and the least squares correction is applied. View the results and if happy create the printable output for your archives. The corrected coordinates are copied back into the precision stadia. Pressing the cancel button will recalculate the coordinates without least squares correction.
The least squares report is shown below:
Using ń 5mm + 3 ppm and 5 seconds
and a Vertical Refraction correction of 0 sec/Km.
Fixed Points
Point Easting Northing Height
1 347113.545 6361334.291 90.373
2 347166.813 6361107.535 99.169
8 347340.490 6361421.048 91.082
Reduced Directions Approximate Coordinates
At To Horizontal Vertical Distance HOI HOT Point Easting Northing Height
1 2 166.4649 87.5923 233.099 1.903 1.295 2 347166.812 6361107.538 99.162
1 3 70.4332 89.4946 247.457 1.903 1.555 3 347347.101 6361415.965 91.462
1 5 342.2659 90.4702 239.605 1.903 1.295 5 347041.309 6361562.693 87.707
1 4 344.2216 90.5328 183.644 1.903 1.295 4 347064.082 6361511.101 88.127
3 1 250.4332 90.1024 247.456 1.550 1.903 1 347113.546 6361334.291 90.364
3 6 85.1346 90.1056 139.022 1.550 1.545 6 347485.623 6361427.525 91.026
3 7 346.0118 92.2919 88.312 1.550 1.295 7 347325.791 6361501.570 87.883
3 8 307.3836 94.2239 8.360 1.550 1.295 8 347340.501 6361421.055 91.079
6 3 265.1346 89.4905 139.021 1.543 1.550 3 347347.102 6361415.965 91.462
6 9 345.3616 91.1318 112.764 1.543 1.542 9 347457.598 6361536.710 88.624
6 10 166.3845 87.2555 120.935 1.543 1.295 10 347513.524 6361309.993 96.694
9 6 165.3616 88.4645 112.765 1.540 1.543 6 347485.623 6361427.524 91.024
9 7 255.0352 90.2454 136.426 1.540 1.295 7 347325.801 6361501.554 87.882
9 11 271.5558 90.3815 55.210 1.540 1.295 11 347402.430 6361538.571 88.255
7 9 75.0352 89.4718 136.432 1.527 1.295 9 347457.606 6361536.712 88.619
7 3 166.0111 87.4928 88.289 1.527 1.295 3 347347.113 6361415.952 91.466
7 13 11.2802 90.0429 86.710 1.527 1.587 13 347343.037 6361586.522 87.709
7 12 43.2902 90.4642 34.317 1.527 1.295 12 347349.411 6361526.447 87.648
13 7 191.2802 89.5531 86.713 1.587 1.527 7 347325.800 6361501.551 87.883
13 14 268.1257 90.3030 84.735 1.587 1.515 14 347258.357 6361583.884 87.030
13 15 278.0726 92.4425 7.590 1.587 1.295 15 347335.533 6361587.593 87.638
14 13 88.1257 89.2938 84.735 1.510 1.587 13 347343.037 6361586.522 87.702
14 16 98.5120 89.5548 67.778 1.510 1.295 16 347325.319 6361573.451 87.328
14 17 81.1058 89.4828 62.654 1.510 1.295 17 347320.263 6361593.487 87.455
14 18 83.5118 89.5649 42.912 1.510 1.295 18 347301.017 6361588.477 87.285
14 19 97.5244 92.1127 14.518 1.510 1.295 19 347272.726 6361581.896 86.690
14 20 157.3748 96.5429 5.807 1.510 1.295 20 347260.551 6361578.554 86.546
14 21 174.0349 90.0957 56.782 1.510 1.295 21 347264.229 6361527.414 87.081
14 22 258.0954 90.1350 86.951 1.510 1.543 22 347173.266 6361566.053 86.648
22 14 78.0954 89.4617 86.953 1.538 1.515 14 347258.359 6361583.884 87.018
22 4 243.1610 89.1725 122.260 1.538 1.590 4 347064.094 6361511.072 88.111
22 23 188.2416 89.2759 69.242 1.538 1.370 23 347163.148 6361497.566 87.461
22 24 204.1335 89.5821 73.149 1.538 1.300 24 347143.254 6361499.355 86.921
22 25 168.5035 89.5926 58.365 1.538 1.300 25 347184.558 6361508.798 86.895
22 26 154.4705 90.0503 59.540 1.538 1.300 26 347198.628 6361512.193 86.798
22 27 149.0923 90.1712 41.387 1.538 1.300 27 347194.482 6361530.524 86.679
22 28 135.0314 90.4527 22.698 1.538 1.300 28 347189.298 6361549.992 86.585
22 29 110.2831 91.1455 14.634 1.538 1.300 29 347186.971 6361560.936 86.567
22 30 90.3622 90.3128 32.052 1.538 1.300 30 347205.311 6361565.714 86.592
22 31 85.2335 90.3955 49.362 1.538 1.300 31 347222.459 6361570.017 86.313
22 32 136.4128 89.1246 96.773 1.538 1.300 32 347239.049 6361495.102 88.216
4 1 164.2216 89.2344 183.628 1.587 1.295 1 347113.556 6361334.266 90.342
4 5 336.1046 90.4318 56.409 1.587 1.295 5 347041.317 6361562.665 87.693
4 22 63.1627 90.4244 122.262 1.587 1.540 22 347173.273 6361566.045 86.639
4 41 329.4600 90.2816 26.972 1.587 1.300 41 347050.515 6361534.372 88.176
4 42 327.0742 90.4727 16.234 1.587 1.300 42 347055.285 6361524.704 88.174
4 33 312.5825 91.0259 7.767 1.587 1.300 33 347058.413 6361516.365 88.256
4 34 237.2932 91.4401 3.457 1.587 1.300 34 347061.181 6361509.215 88.293
4 35 181.1859 90.4207 8.913 1.587 1.300 35 347063.890 6361502.163 88.289
4 36 173.1430 90.1442 14.965 1.587 1.300 36 347065.855 6361496.213 88.334
4 37 168.4647 90.0639 29.112 1.587 1.300 37 347069.758 6361482.520 88.342
4 38 167.2409 89.5642 50.347 1.587 1.300 38 347075.074 6361461.943 88.446
4 39 107.0107 91.1209 59.484 1.587 1.300 39 347120.954 6361493.668 87.150
4 40 113.0424 94.4332 10.311 1.587 1.300 40 347073.547 6361507.045 87.548
Misclose
At To deast dnorth dheight
1 2 -0.0006 0.0027 -0.0112
1 3 0.0000 0.0000 -0.0042
1 5 0.0000 0.0000 -0.0039
1 4 0.0000 0.0000 -0.0023
3 1 0.0010 0.0003 -0.0128
3 6 0.0000 0.0000 -0.0013
3 7 0.0000 0.0000 -0.0005
3 8 0.0112 0.0068 -0.0033
6 3 0.0010 0.0001 -0.0014
6 9 0.0000 0.0000 -0.0009
6 10 0.0000 0.0000 -0.0010
9 6 0.0003 -0.0010 -0.0028
9 7 0.0097 -0.0161 -0.0022
9 11 0.0000 0.0000 -0.0002
7 9 -0.0014 0.0183 -0.0049
7 3 0.0021 0.0040 0.0045
7 13 -0.0097 0.0161 0.0005
7 12 -0.0097 0.0161 0.0009
13 7 0.0092 -0.0190 -0.0005
13 14 0.0000 0.0000 -0.0005
13 15 0.0000 0.0000 -0.0000
14 13 0.0000 0.0000 -0.0078
14 16 0.0000 0.0000 -0.0003
14 17 0.0000 0.0000 -0.0003
14 18 0.0000 0.0000 -0.0001
14 19 0.0000 0.0000 -0.0000
14 20 0.0000 0.0000 -0.0000
14 21 0.0000 0.0000 -0.0002
14 22 0.0000 0.0000 -0.0005
22 14 0.0020 0.0004 -0.0124
22 4 0.0119 -0.0293 -0.0173
22 23 0.0000 0.0000 -0.0003
22 24 0.0000 0.0000 -0.0004
22 25 0.0000 0.0000 -0.0002
22 26 0.0000 0.0000 -0.0002
22 27 0.0000 0.0000 -0.0001
22 28 0.0000 0.0000 -0.0000
22 29 0.0000 0.0000 -0.0000
22 30 0.0000 0.0000 -0.0001
22 31 0.0000 0.0000 -0.0002
22 32 0.5821 0.5487 -0.0006
4 1 -0.0010 0.0039 -0.0166
4 5 -0.0047 0.0017 0.0019
4 22 -0.0057 0.0211 0.0070
4 41 -0.0119 0.0293 0.0163
4 42 -0.0119 0.0293 0.0163
4 33 -0.0119 0.0293 0.0163
4 34 -0.0119 0.0293 0.0163
4 35 -0.0119 0.0293 0.0163
4 36 -0.0119 0.0293 0.0163
4 37 -0.0119 0.0293 0.0162
4 38 -0.0119 0.0293 0.0161
4 39 -0.0119 0.0293 0.0161
4 40 -0.0119 0.0293 0.0163
Point East Adj Adj.East North Adj Adj.North Height Adj Adj.Height
1 347113.545 6361334.291 90.373
2 347166.813 6361107.535 99.169
8 347340.490 6361421.048 91.082
3 347347.101 -0.0047 347347.0960 6361415.965 -0.0024 6361415.9621 91.462 0.0035 91.4653
5 347041.309 -0.0039 347041.3056 6361562.693 -0.0025 6361562.6903 87.707 0.0033 87.7101
4 347064.082 0.0001 347064.0824 6361511.101 -0.0059 6361511.0954 88.127 0.0031 88.1303
6 347485.623 -0.0075 347485.6153 6361427.525 0.0004 6361427.5255 91.026 0.0023 91.0283
7 347325.791 -0.0049 347325.7864 6361501.570 -0.0065 6361501.5632 87.883 0.0024 87.8851
9 347457.598 -0.0083 347457.5895 6361536.710 0.0077 6361536.7175 88.624 0.0023 88.6259
10 347513.524 -0.0075 347513.5162 6361309.993 0.0004 6361309.9938 96.694 0.0013 96.6949
11 347402.430 -0.0083 347402.4213 6361538.571 0.0077 6361538.5791 88.255 0.0021 88.2566
13 347343.037 -0.0139 347343.0233 6361586.522 0.0157 6361586.5375 87.709 0.0035 87.7127
12 347349.411 -0.0146 347349.3964 6361526.447 0.0096 6361526.4570 87.648 0.0033 87.6509
14 347258.357 -0.0118 347258.3456 6361583.884 0.0164 6361583.9003 87.030 0.0078 87.0376
15 347335.533 -0.0139 347335.5191 6361587.593 0.0157 6361587.6087 87.638 0.0035 87.6418
16 347325.319 -0.0118 347325.3072 6361573.451 0.0164 6361573.4677 87.328 0.0074 87.3354
17 347320.263 -0.0118 347320.2510 6361593.487 0.0164 6361593.5029 87.455 0.0075 87.4628
18 347301.017 -0.0118 347301.0056 6361588.477 0.0164 6361588.4933 87.285 0.0076 87.2924
19 347272.726 -0.0118 347272.7143 6361581.896 0.0164 6361581.9119 86.690 0.0077 86.6976
20 347260.551 -0.0118 347260.5394 6361578.554 0.0164 6361578.5700 86.546 0.0078 86.5542
21 347264.229 -0.0118 347264.2176 6361527.414 0.0164 6361527.4302 87.081 0.0075 87.0883
22 347173.266 -0.0107 347173.2556 6361566.053 0.0171 6361566.0702 86.648 0.0143 86.6619
23 347163.148 -0.0107 347163.1370 6361497.566 0.0171 6361497.5834 87.461 0.0140 87.4747
24 347143.254 -0.0107 347143.2433 6361499.355 0.0171 6361499.3717 86.921 0.0140 86.9350
25 347184.558 -0.0107 347184.5477 6361508.798 0.0171 6361508.8155 86.895 0.0141 86.9095
26 347198.628 -0.0107 347198.6177 6361512.193 0.0171 6361512.2104 86.798 0.0141 86.8124
27 347194.482 -0.0107 347194.4717 6361530.524 0.0171 6361530.5415 86.679 0.0142 86.6928
28 347189.298 -0.0107 347189.2870 6361549.992 0.0171 6361550.0086 86.585 0.0143 86.5998
29 347186.971 -0.0107 347186.9601 6361560.936 0.0171 6361560.9530 86.567 0.0143 86.5810
30 347205.311 -0.0107 347205.3004 6361565.714 0.0171 6361565.7312 86.592 0.0143 86.6065
31 347222.459 -0.0107 347222.4486 6361570.017 0.0171 6361570.0342 86.313 0.0142 86.3267
32 347239.049 0.5715 347239.6207 6361495.102 0.5658 6361495.6674 88.216 0.0137 88.2294
41 347050.515 -0.0119 347050.5035 6361534.372 0.0234 6361534.3950 88.176 0.0193 88.1955
42 347055.285 -0.0119 347055.2731 6361524.704 0.0234 6361524.7271 88.174 0.0194 88.1932
33 347058.413 -0.0119 347058.4012 6361516.365 0.0234 6361516.3883 88.256 0.0194 88.2750
34 347061.181 -0.0119 347061.1687 6361509.215 0.0234 6361509.2386 88.293 0.0194 88.3127
35 347063.890 -0.0119 347063.8777 6361502.163 0.0234 6361502.1865 88.289 0.0194 88.3081
36 347065.855 -0.0119 347065.8433 6361496.213 0.0234 6361496.2364 88.334 0.0194 88.3533
37 347069.758 -0.0119 347069.7464 6361482.520 0.0234 6361482.5435 88.342 0.0193 88.3610
38 347075.074 -0.0119 347075.0618 6361461.943 0.0234 6361461.9667 88.446 0.0192 88.4656
39 347120.954 -0.0119 347120.9419 6361493.668 0.0234 6361493.6916 87.150 0.0192 87.1690
40 347073.547 -0.0119 347073.5351 6361507.045 0.0234 6361507.0687 87.548 0.0194 87.5679
Residuals
At To Horizontal Corr Distance Corr
Stn.Stn. secs.
1 2 166.4649 -0.000 232.929 0.0028
1 3 70.4332 0.583 247.419 -0.0053
1 5 342.2659 -3.865 239.551 -0.0012
1 4 344.2216 -1.717 183.593 -0.0057
3 1 250.4332 0.646 247.419 -0.0042
3 6 85.1346 -4.511 139.001 -0.0025
3 7 346.0118 -2.631 88.214 -0.0039
3 8 307.3836 -184.723 8.337 0.0025
6 3 265.1346 -4.502 139.001 -0.0015
6 9 345.3616 1.855 112.731 0.0072
6 10 166.3845 -0.000 120.798 -0.0000
9 6 165.3616 1.940 112.731 0.0062
9 7 255.0352 5.274 136.411 0.0056
9 11 271.5558 0.000 55.200 0.0000
7 9 75.0352 5.247 136.411 -0.0030
7 3 166.0111 4.435 88.214 -0.0006
7 13 11.2802 -1.213 86.705 0.0060
7 12 43.2902 -0.000 34.309 0.0000
13 7 191.2802 -1.147 86.705 0.0030
13 14 268.1257 1.594 84.719 -0.0022
13 15 278.0726 -0.000 7.580 -0.0000
14 13 88.1257 1.592 84.719 -0.0022
14 16 98.5120 -0.000 67.769 -0.0000
14 17 81.1058 -0.000 62.646 0.0000
14 18 83.5118 0.000 42.907 -0.0000
14 19 97.5244 -0.000 14.506 -0.0000
14 20 157.3748 0.000 5.764 0.0000
14 21 174.0349 -0.000 56.775 -0.0000
14 22 258.0954 1.132 86.938 -0.0012
22 14 78.0954 1.118 86.938 -0.0032
22 4 243.1610 10.343 122.233 -0.0017
22 23 188.2416 -0.000 69.230 0.0000
22 24 204.1335 -0.000 73.140 0.0000
22 25 168.5035 0.000 58.358 0.0000
22 26 154.4705 0.000 59.532 -0.0000
22 27 149.0923 -0.000 41.381 -0.0000
22 28 135.0314 -0.000 22.693 -0.0000
22 29 110.2831 -0.000 14.629 -0.0000
22 30 90.3622 -0.000 32.047 -0.0000
22 31 85.2335 0.000 49.352 -0.0000
22 32 136.4128 0.000 96.752 0.0000
4 1 164.2216 -1.580 183.593 -0.0017
4 5 336.1046 4.835 56.399 0.0013
4 22 63.1627 -6.700 122.233 -0.0037
4 41 329.4600 0.000 26.968 0.0000
4 42 327.0742 0.000 16.230 0.0000
4 33 312.5825 -0.000 7.765 -0.0000
4 34 237.2932 0.000 3.455 0.0000
4 35 181.1859 0.000 8.911 0.0000
4 36 173.1430 0.000 14.963 0.0000
4 37 168.4647 0.000 29.108 0.0000
4 38 167.2409 0.000 50.341 0.0000
4 39 107.0107 -0.000 59.463 -0.0000
4 40 113.0424 -0.000 10.275 -0.0000
We can now store the corrected points into the CDS database.