Several stations only are repeated in each loop. In such a case, "Maximum polynom degree for drift calculations" parameter in Project properties should be limited to "1", i.e. instrument drift is expected to be linear during the loop data acquisition;

Drift correction value for the last station reading of the day presented in the Loop report of each loop represents total residual drift of the instrument during the survey day. This value should be similar for consecutive days taking into account total acquisition time of a survey day. Irregularities in the instrument drift behavior can signal instrument problem or improper handling of the instrument;

Standard deviation of the overall loop closure precision is represented in the "Processing status" item of the Loop report header. This value is computed from residuals of all in-loop repetitions including base station readings after drift corrections were applied. This value is an indicator of quality of data acquisition of the particular loop.

Columns "Number of obs.", "RMS" and "Max. error" in the Stations results summary table represent statistics of stations repetitions for the entire project. Maximum repetition error of the cross-loop repeated stations represents independent check of the reliability of the data acquisition and pre-processing.

Terrain corrections computed using the Plouff prism method in a 3 arcSec SRTM data grid were applied at the final processing stage. It is evident from the results, that terrain corrections have principal influence on the results in a given area. Please note, that the block containing the particular station is excluded from the Plouff corrections computation. In order to obtain results of maximum precision, in addition to the corrections computed by the software, near-zone terrain corrections corresponding approx. to zones A, B and C of the Hammer sheet should be computed manually and final results should be corrected for the near zone terrain influence. At this moment, software does not have a tool for the near zone corrections.

Stations coordinates were provided in ellipsoidal elevation datum while SRTM data are referenced to geoidal datum. Parameter "SRTM Difference" in Project settings represents elevation datum difference. Software can compute this value automatically as a mean of differences of interpolated SRTM elevations and provided stations elevations over all survey stations. Button "Compute difference" in Project properties performs this computation and newly computed value is filled-in into the Project properties. If your elevation data are referenced to geoidal heights, the computed difference should represent the SRTM interpolation uncertainty and should be small, usually less than 5 meters.

Each loop consists of several observations on both reference and newly established base. At least three observations at the reference and two observations at each tied station are highly desirable in order to model the instrument drift as precisely as possible;

Because of many repetitions available during the span of each loop, "Maximum polynom degree for drift calculations" parameter in Project properties can be set to a higher value, 2 or 3 depending on the number of repetitions and loops time span;

Because of very long instrument transportation often in uneven conditions, recovery effect takes place at each station occupation. After setting up the instrument, typically 5-30 minutes delay is desirable in order to let the instrument recover. If readings take place during recovery, instrument behavior can be monitored and optimum recovery time can be selected;

Absolute gravity values at newly established stations are the only interesting results, no gravity reductions are necessary. All columns containing gravity reductions can be turned off in the Loop report by un-checking of appropriate options in the "Output and reporting" tab of the Project properties dialog.