Setting apertures interactively

The commands SNAFU/A and SNAFU/B are used to determine the positions of apertures A and B interactively. For example, when an object has been located on a particular detector pixel, one might want to keep the offset for future use.

1. Position the object on the SNAFU reference point.
2. Type at the User Interface:

   SNAFU/A

3. Move the object to the intended position of aperture A using the handset or guide buttons.
4. Press the ACK button (acknowledge) on the telescope Control Desk.
5. Press the BEAMSWITCH NOM button to return the star to the reference point.
6. If wanted, repeat the procedure for aperture B.

Hereafter, pressing the BEAMSWITCH A or B button will cause the offset to be made. If you want to record the offsets for future reference, inquire their values by typing at the User Interface:

AD(VISE)/TEL(ESCOPE)