The Relative Effectiveness of Red and White Light for Subsequent Dark-Adaptation

Acceptability of Low Level White Lighting in the Sonar Room at Sea

“…We pointed out that few people know how to equate different colors for brightness at the mesopic or scotopic light-levels typically found in sonar rooms (9,10) using a , photometer. When this was done properly, detection performance tended to be slightly better under the LLW light than under the blue lighting (11,12). Although performance was better under the white compared to the blue lighting, the crews still demonstrated a preference for the blue lighting.…”

Immediate Visibility after Red and White Adaptation

“…The advantages of red light for subsequent dark adaptation have been the subject of many investigations (4).…”

Effect of Extreme Peripheral Light on Dark Adaptation

“…A large body of experimental work has clearly established that dark adaptation is faster after exposure to red than to white light [1], Moreover, it is well known that when an observer is adapted to a high intensity of light, it takes about half an hour to reach a state of more or less complete dark adaptation [2], Consequently, it has long been standard procedure aboard submarines to turn on red lights or put on red goggles half an hour before night vision will be required. The periscope operator would prefer all ambient light to be extinguished-and this is often done-but it is not always feasible to do so in the control room, because the other crewmen require some light to carry out their duties.…”