2014 Lights Shootout, Bike Light, Duo 1500, Gemini, Lights, Lights Shootout - October 20, 2013

Review: Gemini Lights Duo 1500

The Gemini Duo is ideal for helmet mounting as it it provides a lightweight head, very similar to the Lupine Piko 4. It throws out a nice 1208 Lumen beam pattern for a run time of 1:30.

Specifications

Price: $230
Claimed Lumens: 1500 Lumens
Measured Lumens: 1208 Lumens
Measured MTBR Lux: 118 Lux
Lumens per $: 5.25 Lumens
Lumens per gram: 3.82 Lumens
Time on High: 1:30 Hours
Charge Time: 2:00 Hours
Mounted Weight: 316 grams
Category: High End

Strengths

Such a small yet bright package
Configurable battery options makes for a custom setup for on helmet battery mounting or long run time
Excellent craftsmanship with a solid company supporting the product
Versatile mount allows it to be mounted on the helmet or bars easily
Excellent switch action. Good programmability options
Clean optics and consistent beam pattern with no hot spots

Weaknesses

1208 measured Lumens is lower than 1500 Lumen claims
Looks a lot like the Lupine Piko
Green switch light is always on and is quite bright

Mounting

Mounting is a very simple helmet strap and a rubber band system. The band allows the light to be tilted up and down easily. The helmet mount is on near the front of the helmet so it is pretty low profile and doesn’t stick up so high where it can get caught in low-hanging branches. Because of the band mounting system, it can be mounted on the bars too.

Mtbr Light Meter Measurements

This light measured 118 Lux on our ambient light measurement facility. The light output measurement is performed by placing a Lux light meter beside the light. Both are pointed at the ceiling (five feet above) of a dark room. This measurement uses the ambient light produced by the bike light.

Integrating Sphere Measured Lumens

This light measured 1208 Lumens in an integrating sphere. Claimed Lumens by the manufacturer is 1500 Lumens. The Lumen-hour graph below shows how the light performs over the first three minutes of its battery cycle.

Compare all Lumen Tests here »

Tunnel Beam Pattern Photo

The location is useful since it has walls and a ceiling that can display a bike light beam pattern. The walls have a lot of graffiti on them and actually show detail when they are lit up by a light with a wide angle. Cones and targets are set up with the far target set up at 120 feet.