Set-up(TOTALSTAION)

Choose an adequate instrument station as described above. In detail, ensure that you can safely operate the instrument without knocking it over. It is necessary to have the center of the instrument, which is the point of intersection of the transverse axis and the vertical axis of the instrument, directly over a given point on the ground (the Instrument Station). Also, the circle and the transverse axis must be horizontal (Moffitt, 1987). Remove the yellow plastic cap from the tripod, and leave the instrument in the case until the tripod is nearly level (see below). The tripod legs are spread (not too vertical) and their points are placed so that the tripod is approximately horizontal and the telescope is at a convenient height for sighting (this is important: you don't want to get a sore back from it being too low, nor do you want to get sore calves and fall over from it being too high). The instrument should be within 20 cm of the desired point, but no extra care is taken to set it up closely at once. If the location of the instrument station is not predetermined, set up first, and then use the optical plummet to locate the benchmark: this will save time, because it takes extra care to accurately set up over a benchmark. When setting up on rough ground, two legs of the tripod should be set at about the same elevation and the top of the tripod is made level by changing the length of the third. Consider the common sighting direction and try to have one leg pointing that way so that there will be a gap between two legs behind, and the instrument operator will not have to straddle a tripod leg for the entire session. If the instrument is more than a few inches from the given point, the tripod is shifted bodily without changing the inclination of the legs and it is set near as possible to the point. Check the level by placing a Brunton compass on top of the tripod and adjusting gently until the Brunton bubble level indicates that the top of the tripod is level. Tread tripod shoes firmly into the ground, making sure to press along the leg and not verically down (Anderson and Mikhail, 1989). If shoes do not penetrate to an equal depth, re-level by extending or retracting the tripod legs. Before attaching the instrument, check that the clamps of the telescopic legs are tight.
Once the tripod is nearly level and nearly above the desired point, remove the Theodolite gently from its case and carry it with one hand on the upper handle, and one hand below, to the top of the tripod, and immediately screw the tripod fixing screw firmly into the bottom of the theodolite. The levels on the instrument are very sensitive, and therefore, the instrument should be completely set up in order to ensure that it will be properly leveled. This will also give the tripod more time to thermally equilibrate with the atmosphere and incident sunlight, since differential thermal expansion of the tripod legs will effect the levels.
Now you are ready for fine leveling of the instrument. Use the three black footscrews on the tribrach (the device on the bottom of the Theodolite to which the tripod fixing screw is attached) to center the circular bubble. This is a coarse level. Turn the outer ring on the eyepiece of the optical plummet until the crosshairs are in focus. Turn the inner ring of the optical plummet until the ground point is in focus. Slacken tripod fixing screw and move instrument over tripod plate until cross hairs coincide with ground mark