Computation of SDA, SDB and SDC for Azimuth Observations

Instrument                       Instrument Code                 SDA (sec)
Instrument Description            Observation           SDA     SDB     SDC
and Procedure                         Code             (sec)   (sec)   (sec)
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First order azimuths observed        53 yr              0.8     0.2     1.5
prior to 195 (before the DKM3
or T4 were used by GSD
   yr = year of survey

Azimuths observed during and         53 yr
after 1956:

   Wild T4, 24 obs, 2 nights, 6 sets/position           0.8     0.2     1.0
   Kern DKM3, 32 obs, 2 nights, 6 sets/posiiton         0.8     0.2     1.0
   Kern DKM3A, 32 obs, 2 nights, 6 sets/position        0.8     0.2     1.0
   Kern DKM3A, 16 obs, 1 night, 3 sets/position         1.0     0.4     1.4
   Wild T3, without striding level                      0.8     1.5     1.0
   Wild T2, with striding level                         2.0     1.2     1.0
   Wild T2, without striding level                      2.0     5.0     1.0

Miscellaneous lower-order azimuths:

   Lower-order azimuth on Polaris    53POL       2.0 to 5.0     0.0     0.0
     (no astro position)
   Sun shot                          53SUN             20.0     0.0     0.0
   Computed azimuth                  53AZI or INV       1.0     0.0     0.0

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Created 6 Dec 98 by Mike Craymer