Electronics, Lighting, & Gadgets - 150 lumen brighter than 250??
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freeranger
12-06-08, 10:10 AM
I know little about electronics, but it would seem to me that 230 Lumens should be brighter than 150. But I have a Smartfire V-68C 150 lumen flashlight that, with the same 18650 battery, is brighter on high than an Ultrafire WF-501B(rated at 250 lumens). The Smartfire uses a Q-5 emitter, while the UF uses an R2-WC emitter. They are close to the same brightness on high, but the Smartfire is a bit brighter. Does a Q-5 emitter make that much difference, or is the UF just overrated?
Most likely the "250" (or 230) lumens is the bulb (theoretical) output for the Ultrafire, whereas the 150 lumens for the smartfire is the true output. I have a "230" lumen Ultrafire 606a, but in reality it's a bit dimmer than the 180 lumen Fenix L2D.
(Likewise, a P7 isn't even close to 900 lumens)
CathastrophiX
12-06-08, 12:49 PM
The 501B is probably optimized for a higher voltage, try to use two RCR16340 instead (if it's rated to 8,4 volts.)
Lumens are the total light output. If the lower powered unit has a narrower beam than the higher powered unit, it is possible that it will appear brighter at the center of the spot.
Of course, it's also possible that someone lied about their output power.
joshandlauri
12-06-08, 10:09 PM
.
Of course, it's also possible that someone lied about their output power.
what, thats propersterous, people would never lie about something to sell more stuff ;)
freeranger
12-06-08, 10:13 PM
The 501B is probably optimized for a higher voltage, try to use two RCR16340 instead (if it's rated to 8,4 volts.)
That seems like what it might be-does say "Voltage input range: 3V~8.4V"--and can be used with 1 x 18650, or 2 x CR123A, so I had a couple of CR123 (and they were charged to 3V each according to a multimeter, still not any brighter than 1 x 18650. Guess I'll just have to start learning how to read the specs on these LED lights better, and make sure the output is rated for the battery's output that I intend to use. Still a good little light, just not the brightness I was expecting. Maybe I'll have to try one of the P7's or an MC-E, but I'll read the reviews here before purchasing-seems to be a good bit of info here which might help a novice like myself.
mechBgon
12-07-08, 04:24 PM
Beam pattern can be quite important. I lent out my DiNotte 600L and my Fenix L2D Q5 to a co-worker, a very experienced day & night rider. He tried them helmet-mounted, and he prefers the L2D Q5 (145 lumens) over the DiNotte 600L running at 300 lumens (half-power). Why? Because the L2D's beam pattern works better for him. He handed back the 600L and is still using the Fenix, which is what he'll probably buy. This is a guy who'll go on 8-hour off-road rides and multi-day self-supported backcountry rides.
So take lumen ratings with a grain of salt. Even if they're accurate, the final determination is how well you can ride with a given light, and your eyes will adjust to different lumen outputs a lot more easily than they'll adjust to a bad beam pattern :)