Assertion: flashlight's light | /r/HasProperty | needed
Facets:
value: in order to reach an optimum viewing spot
type: PURPOSE
value: in observing fluorescence
type: OTHER
Source sentences:
text: At full power, the unit emits 625 lumens of light up to 1,300 feet (in optimal conditions) or as few as 58 lumens when just a little light is needed.
text: Although many other types of lamp emit ultraviolet light with visible light, black lights are essential when UV-A light without visible light is needed, particularly in observing fluorescence, the colored glow that many substances emit when exposed to UV.
text: This is because looking for constellations should be done in complete darkness whenever possible, yet some light is needed in order to reach an optimum viewing spot.