... the alfa calibration results (.ps) ( .pdf ): . the pointing error vs rotation angle offset (.ps) ( .pdf ): . ... Comparing the two lets you separate out the alfa installation errors with general telescope pointing problems (from the beam repair). ... Part of the pointing error could come from the alfa rotation angle being off. ... Compute the change in the pointing error if the alfa rotation error was off by -5 to +5 degrees in .1 degree steps. ... Top: rms pointing error vs rotation angle offset. ...