REFA Movement As Rotator Moves

Note: these images are of the old PXL annular guider, but the effect is the same with the MAGIQ guider.

Drive Angle 0	Drive Angle 41

These pictures illustrate the movement of the REFA pointing origin as the rotator moves. The star circled in green is at REFA in each case. The "drive angles" referred to in the captions are the values shown on FACSUM for each position (not the rotator physical angle as reported on the NIRSPEC image rotator GUI).

With the rotator at drive angle = 0, which also happens to correspond to physical angle =0 on the NIRSPEC rotator GUI, REFA is at the 12 o'clock position.

With increasing drive angle as reported on FACSUM, REFA circles around the annulus in the anti-clockwise direction.