Reducing the lights before jumping
Customary practice performed by some starship pilots before entry into jumpspace.
The transitions to and from jumpspace are momentous occasions during an interstellar trip. Historically, most of a starship's power was diverted into the computer and jump drive systems, so that the jump drive could be guided into creating the jump field properly.
The practive of dimming the ship's lights before jump has evolved into a Vilani superstition. Most Vilani-trained pilots will dim the ship's interior and exterior lights before going into jump. Lights are typically dimmed for a period of about two minutes; the lights are brought back up to full strength as soon as the ship is in jumpspace.
Zhodani and Solomani pilots do not follow this tradition of "jump dimming".