Has anyone noticed that the brightness seen when first turned on dims fairly quickly over 30-40 minutes even with most powerful batteries?
994915
I have not noticed that problem with mine. I did contact customer service after another purchase however and they were very accomadating. Their email contact info is on a previous post on Amazon.
994916
Here is the customer service contact info@brightmedic.com-- they were great.
994917
I have not seen any diminishment in the brightness. This has been a great pocket light for me. Totally happy with it.
1549082
I am not sure? I know it is super bright when you first turn it on and then it seems to fade a bit... never too dark but not as bright as the first couple of minutes. ..
433310
Not exactly sure, but had a new set in and left it on high mode for 3hours straight and did not dim. Fwiw
191509
i'm not sure... but when the batteries are getting low, the brightest beam only works for a split second, & the lower beam only works for under a minute. new batteries will make it like new.
865364
Mine does the same thing. I unscrewed the bottom cap and the top cap (not the head where the light is) wiped all battery contact surfaces and now it is better but sometimes comes on dim. This would suggest it's a manufacturing problem and not necessarily the switch. However, I wouldn't rule that out as the whole unit is not the best quality I have seen in these types of flashlights. I guess you get what you pay for.
91954
I think so. The lights are very bright once you have new batteries. They do get dimmer as the batteries wear down, I cannot say how long a set of batteries will last when the light is on for eight or more hours. It's your call, but they are bright enough to light a display.
1579076
The battery life is rated at 43 hours on high power, and up to 150 hours with the use of the dimming feature to balance amount of light with battery life. The key feature that extends the battery life of our headlamp beyond that of competitors is you are able to set the exact light that you need. Often (such as reading in bed or in the tent), you simply don't need full power. Our efficient LED bulbs maximize battery life by using less battery power if you're using less light. Note: As with all headlamps, you will see some dimming as batteries become weak and this is an indication to replace or even better recharge. Finally, if you are storing the headlamp in a cold place, store the batteries separately as leaving batteries in any headlamp during cold storage will drain the batteries. Thanks for your question and we hope you decide to become a valued Northbound Headlamp customer!
348703
Once the bulb starts which takes about a half a second dimming is immediate.
11205
I have not had or used this long enough to find out. I think the LEDs current draw is low on the four D cells. Hasn't dimmed in about half hour total on time so far. I suspect it would run much longer than a light with an incandescent bulb.
144711
I also bought a refurb and love it. I went into the settings and turned brightness way down but its still seems plenty bright. You can check in settings and see which programs are the biggest drain. Turning off Bluetooth will also help. I think companies always overestimate how much battery life they can achieve (they probably measure the life by how long you can listen to mp3's continuously). I don't think you should be concerned.
1157574
I'm getting a lot more than the other answers so far. I keep the display a couple ticks below maximum brightness most of the time, which helps, but I get a good eight hours.
787933
I have not actually "test" how long a full changed battery can last. But after I used it for nightly walk several times a week ( not on for all the walk, only a few minutes per walk, but when it's on it is with full brightness ) about three months later I found the brightness is weakening. I know it is not a very scientific way of "testing", but that's what I know about the battery. It is decent but not great as far as battery usage goes. Hope it helps.
625217
I have been using the light on a bicycle with a 12 volt battery-however, as noted in my prior review, the light has dimmed far below the original brightness for unknown reason within six weeks of purchase.
2203143
It uses LEDs which should not dim from use. My only concern would be the battery's ability to fully charge after 1000 cycles (3 years) or so.
1392491
Very poor. I did a battery test with a brand new energizer and left it on at 60% brightness level. After 40 hours, it was already dead.
1866348
While I have not specifically timed battery life under high or low settings, my observations are that on the high setting, the light lasts on the order of several hours but the brightness decreases fairly early on. The light still provides useable light when the brightness wanes but do not expect the light to be "300 lumens" for more than an hour or two. I do not use the light on the low setting.
1870501
Now that I have had my light for about a month, I find that the batteries do not maintain their power level like they did when they were new. I was getting about 8-10 hours on low setting, and now it is barely 8 hours. Still, much better then something like the Brinkman's which run on 3 AAA batteries at 1/4 the output power at about the same price. I purchased two lights so I can have one charging while one is in use. This works very good, and it gives me another light in case something happens to one of them.