Figure 5. This shows the axial sag of the 3.5-m secondary on all three of the secondary actuators. ... The axial sag in the C axis is about 3 times that seen in A and B as evidenced by the m1 values given in the fits to each data set. Note that the arbitrary zero point on this graph is simply set to the axial sag measured at the lowest elevation angle in the data set, but the inclusion of m3 in the form of the equation fit to the data was designed to account for this. ...