BOY, is lighting design time-consuming! First there are image searches, which take hours to yield a few useful images for "design inspiration." Then you have to apply your ideas to actual lights. One of our final projects is to create a lighting design for West Side Story and go into the light lab - essentially a tiny black-box "theater" with a slew of lights and accessories to experiment with - to apply that design to one of the songs from the show. We're all paired off, chiefly for efficiency (e.g., one can stand in a focus point while the other focuses a light) and safety (that 20-foot ladder is definitely a 2-person lift). My partner met me this morning for our 8-noon block in the light lab. He left for class afterwards, but I stayed to keep working. I finally left around 6 pm to go home for dinner, then went back for another hour and a half. For those keeping score, I left for campus about 7:30 this morning, stayed till 6 pm (I did allow myself a lunch break) to have dinner with the Chief, then went back to finish up. I got home to stay around 10 pm.
Even subtracting a couple of hours for trouble-shooting, I spent nearly 10 hours writing cues for a song that's all of about 2:34 minutes long!