Planet Bike makes LED based headlights that are bright and quite good value. I’ve had the 1W version for a while. It is an excellent “to be seen” light, especially in the annoying flash mode. It is hard for me to tell if it is a good standalone headlight, since I cycle in the city where there are almost always streetlights. I will say that the light has a rather tightly focused beam. If I was out in the country, I would prefer a more spread out beam, like the one I get with my old B&M Lumotec.
When they came out with the 2W version, the thing that I wanted to know what was how the 2W low power mode compared with the 1W bright mode, so that I might get a longer run time with the 2W lamp.
Over the last couple of days, I’ve run some simple tests.
Here the the two lamps, with the white 1W in the background, and the black 2W in the foreground.
Here are the lamps shining on my garage door.
Here are the spots, in the dark, after 9 hours of running. The left hand spot is the 1W at full power, and the right hand spot is the 2W at low power. The short answer is that the 2W at low power is brighter than the 1W at high power.
Now a word about run times. According to the Planet Bike website, the 1W and 2W have run times of 7/14/20 (low/high/flash) and 5/12/18 hours, respectively. My interest was in seeing how the 1W on high compared with the 2W on low.
The first time I tried this, I used a fresh pack of precharged rechargeables from Eveready. Both lights (1W on high and 2W on low) ran overnight, and they died sometime between hours 6.5 and 11.
The second time I tried this, I fully recharged the batteries and started the test earlier in the day so that I could see the behaviour over the entire run time. Surprisingly, both lights ran 12 hours while I was awake and then were dead in the morning.
Four lessons from this:
1) the 2W on low is brighter than the 1W on high.
2) precharged batteries appear not to be fully charged.
3) the 1W runs surprisingly long on high mode?
4) although I was never awake when either light died, I have the suspicion that they might dim rather quickly towards the end of their run times. I certainly did not see much dimming, except for the 1W after 6.5 hours on the first run, whereas for an incandescent battery powered headlight, dimming is readily apparent for the last half to third of battery life. Interestingly enough, I believe that there is a circuit that cuts off power after the batteries drop to a certain voltage, since after the light turns off, the switch gets electronically reset to the off position. (unless one of the raccoons that traipse through our backyard is doing this at 4 in the morning just to mess with my head) Whenever this happens, I am able to get a little more light by turning the lights back on after several hours of rest, but I haven’t bothered to check how much life is left.
Update: I’ve done some more accurate runtime measurements here.