Interpretation of external reliability

Be aware that the gross error detection listed together with external reliability is different from the last one you obtained from gross error detection. This is the case because a free network is used for gross error detection, but not for external reliability. External reliability is usually based on the entire network (control points and observations), while in "ordinary" gross error detection one is usually only interested in possible errors in the observations.

Maximum point deformation

For each of the unknown points in the adjustment, the largest deformation (position change) that a possible remaining gross error can cause is listed, together with requirements that the selected standard imposes.

• The deformation is also split into dX, dY and dZ and given in meters
• The observation that causes this deformation is also shown. More about this observation at the bottom of the result list (under Involved observations)

Maximum deformation on angle/height difference/scale

For each point, known or unknown, the largest impact on angle and scale to a neighboring point is listed. For horizontal calculation, only angle and scale are listed, for height calculation only height difference, and for 3D adjustment all three measures.

• From-point is the designation for one neighboring point while To-point is the designation for the other to which the largest impact factor is listed. For height difference, only To-point is used.
• If Factor is greater than 1.00, the largest impact is above the standard's requirements and the point of interest cannot be approved in the selected quality class.
• Angle, height difference and scale have the unit ppm.

Involved observations

The observations that cause deformation get more detailed documentation here: Where the observation is measured, the size of the observation after all corrections have been applied and the largest remaining gross error it can contain. Everything has the unit gon or meter depending on observation type.