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Moon's Gemini front light is a six-mode model that initially felt impotent compared with some 'office strip light' patterns – especially in the lower settings. However, there is an 80-lumen daylight flash option and the 30-lumen flashing/strobe patterns still offer a very good mix of power and economy.
Available singularly or as a front and rear package, the Gemini has a CNC machined aluminium casing (which also doubles as a heat sink) that houses two 'high power' white LEDs, circuits, switch gear and 3.7-volt 300Amh lithium polymer cell.
Zero to hero fuel-ups take 2 hours 20 mins at the mains – add 10 minutes or so from laptops and tablets. Auto cut-out prevents the cell overcharging and battery life/charge indicators are pretty standard issue these days. I'm pleased to report that the Gemini's proved very accurate and gave plenty of warning before reserves dipped dangerously low.
On that subject, the Gemini has an auto safe mode, which means you're assured of an hour's burn time once the low battery indicator starts winking; it's hardly a novel concept – many lights have a similar failsafe but don't make it a selling point.
The small, clear rubberised switch sits is pretty intuitive to use, although it takes a bit of practice when wearing full-finger gloves – especially generously padded winter types. Pressing the switch for two seconds brings the unit to life, with a memory function defaulting to the last choice, then prod twice in quick succession if you to select something more condition-specific.
Unleashing the full 60-lumen constant mode produces a strong, relatively pure arc of light. It doesn't equal Moon's Aerolite COB in terms of presence but there's just enough bite for nipping through town and well-lit suburban stretches. Arguably fit for purpose, a real world run-time of 2:03 is pretty good and could literally prove a lifesaver should a main light pack up miles from home.
Daytime modes stir mixed emotions in me. On the one hand, I tend to run blinkies during the day three seasons round, but I often wonder if drivers have become so used to it they don't even notice. Nonetheless, the double-flash 80-lumen setting is very effective, right up until dusk, and was still going strong after 23 hours.
In terms of economy, most settings have proved faithful to the quoted run times, allowing for the factory battery caveat. I've achieved 8:02 from the 15-lumen constant. Although this setting is handy for those first 40ft or so, before my Univega's 800-lumen hub dynamo powered lamp has woken up, it's underpowered for my tastes; 30 is better, providing enough light for locating correct Allen/house keys.
Flashing were my defaults – visible to around the 125-150m mark on clear nights; pulsing is assertive rather than aggressive, and works a treat round town, snaring attention at similar range.
A quick word about the brackets... Moon offers the standard butterfly and rubber band combo that has grown on me. Accommodating both standard and aero bar profiles, it can also be mounted vertically, which frees up some handlebar space but produces a shallower pool of light and less presence. The clothing clips are similarly tenacious – useful as tertiary illumination on messenger bag straps where the higher positioning amplifies the moderate output.
It took me a while to fully appreciate its potential, but overall I'm impressed with the Gemini and would recommend it if you wanted a compact but very practical safety light.
Quirky looking but surprisingly useful safety light
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road.cc test report
Make and model: Moon Gemini Front Light
Size tested: n/a
Tell us what the light is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Moon says: 'Gemini provides exceptional additional visibility for your person or bike. The 2 independent high brightness LEDs can be constant, flashing or chase modes.'
Does exactly what it says on the tin. Though not quite on par with the COB breed, it's surprisingly bright and with decent presence and distinctive patterns.
Tell us some more about the technical aspects of the light?
2 high brightness LEDs
* Daytime flash mode
* Auto safe mode - guaranteed 1 hour ride time
* Last mode memorized mode
* Constant, flashing & chase modes
* CNC aluminium case
* 80 lumen daytime flash mode with 20 hour runtime
* Includes universal bracket and belt clip bracket
Simple butterfly bracket and ladder type rubber ring accommodates standard and oversize bar/extension bracket diameters very securely.
Conforms to IPX4 standard, so has taken heavy rains and provocative tickling from the garden hose in its stride.
Very economical in the daylight settings and good run times throughout the range.
Very good taking everything into account, but multi-diode COB designs are noticeably brighter.
Heavier than size might suggest but not a bad thing.
Tell us how the light performed overall when used for its designed purpose
Overall the Moon Gemini took a while to grow on me but has proven a frugal and surprisingly capable secondary light. The daylight mode proved literally brilliant during overcast days, while the 60-lumen constant is just good enough for town work, or scooting home at dusk. Visible to around 100 metres on a clear night, it lacks the retina tickling prowess of the multi-diode COB models. Nonetheless, 30-lumen modes seem optimal for most contexts and the battery-sipping 15-lumen strobe is an ideal dynamo companion on all-nighters.
Tell us what you particularly liked about the light
Quirky but surprisingly capable for such a compact design.
Tell us what you particularly disliked about the light
Nothing, but took me a little while to fully appreciate its capabilities.
Did you enjoy using the light? Yes
Would you consider buying the light? Definitely
Would you recommend the light to a friend? Yes
Use this box to explain your score
Lacks the outright presence of the the COB models but still very bright and, in some respects, more practical.
About the tester
I usually ride: Rough stuff tourer based around 4130 Univega mountain bike frameset My best bike is: 1955 Holdsworth Road Path and several others including cross & traditional road
I've been riding for: Over 20 years I ride: Most days I would class myself as: Experienced
I regularly do the following types of riding: cyclo-cross, commuting, touring, fixed/singlespeed, mountain biking
Shaun Audane is a freelance writer/product tester with over twenty-eight years riding experience, the last twelve (120,000 miles) spent putting bikes and kit through their paces for a variety of publications. Previous generations of his family worked at manufacturing's sharp end, thus Shaun can weld, has a sound understanding of frame building practice and a preference for steel or titanium framesets.
Citing Richard Ballantine and an Au pair as his earliest cycling influences, he is presently writing a cycling book with particular focus upon women, families and disabled audiences (Having been a registered care manager and coached children at Herne Hill Velodrome in earlier careers)