Observing procedure:

The observing procedure using this mode consists of the following steps:

(1)

go to setup field - align mask on setup stars

(2)

go to target field - align check star very crudely on location of check star slitlet

(3)

zero the coordinates and offsets

(4)

find the preselected guide star

(5)

find offset guide star by moving telescope, not guide probe (check the field if needed to make sure it's not crowded). Record offsets to guide star. (This step would be modified if one does not intend to guide in the sky position.)

(6)

return to object field position and align the slitmask by peaking up on the check star. One could leave the guiding on for this procedure and simply peak up using the acquisition TV and `offset inspector'. Once aligned, record this as the object position by setting object position on `nod' gui control

(7)

move to `sky' guide star and center the `sky' guide star in the guide box by moving the telescope, not the guide probe

(8)

set `sky' position on nod gui control

(9)

test the offsets by using `move to object' and `move to sky' on the nod gui

(10)

start exposure