From the Engineering Rack

This is recommended when the focus is grossly out of position, because it provides the only way of driving quickly.

1. Either (a) depress the FOCUS SELECTMANUAL button (the button must be illuminated),
   or (b) select Engineering Mode by pressing the ENGCOMP button.
2. Select FOCUS Fast or Slow motion as appropriate and move the focus using the + or - button. All buttons are found on the Engineering rack.