The brightness of lume depends on several factors, including the type of luminous material used, the amount of light exposure it receives, and the amount of lume applied to the dial, hands, and markers.

Like all photoluminescent materials, lume must first absorb light before it can emit a visible glow in dark conditions.

Maximum brightness is typically achieved after exposure to direct sunlight or other strong UV-rich light sources. Bright artificial lighting may also charge the lume, although generally less efficiently than direct sunlight.

We use different types of Swiss Super-LumiNova® depending on the design requirements of each model. Some watches use BGW9, which offers a bright blue glow and strong nighttime visibility. Other models may use Black lume formulations, which provide a more discreet appearance in daylight but typically produce a less intense luminous effect.

As a result, lume intensity and duration may vary between different watch models and designs. Variations in brightness between components are also possible depending on the amount and application of luminous material.

Differences in lume performance do not necessarily indicate a defect.