- Behind the control room desk, dial the rheostat fully anti-clockwise to zero [[File:rheostat.jpg|80px]]
- Flip the switch in front of it to ''On''
- Dial the rheostat up to 220 '''140 V (- do not exceed that value as you will blow the lamps)''' - this value has decreased from 220 V since new lamps were installed in July 2019
- The lamps on the top end of the telescope should now be on
- Open the mirror cover