The flashlight highlighted the anemone's dazzling luminance, while the setting sun added a sense of atmosphere.
British Dictionary definitions for luminance
a state or quality of radiating or reflecting light
a measure (in candelas per square metre) of the brightness of a point on a surface that is radiating or reflecting light. It is the luminous intensity in a given direction of a small element of surface area divided by the orthogonal projection of this area onto a plane at right angles to the direction L