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Flashlights on Amazon are mostly horrible. Thrunite and their offshoot Wowtac are the only brands I'd buy there, because they sell direct. It's usually better t
by Zak 9y ago
Flashlights on Amazon are mostly horrible. Thrunite and their offshoot Wowtac are the only brands I'd buy there, because they sell direct. It's usually better to order from specialty dealers. It's often cheaper too, as they tend to do outreach on forums, /r/flashlight, etc... and offer standing coupon codes.
Visual identification is usually the best way to tell what LED a light really uses. Here's a chart with photos of a bunch of common ones: http://budgetlightforum.com/node/26665 http://budgetlightforum.com/node/26665
While the lights you find on Amazon making extreme claims about output are almost certainly lying, LED manufacturer datasheets tend to be conservative about how much power LEDs can handle. Typical mains-powered fixtures don't have the sort of heatsinking and thermal paths good flashlights do, and LED manufacturers base their limits on a service life of tens of thousands of hours. You will not use your flashlight for 50,000 hours. Overdriven LEDs aren't rare, especially in enthusiast-oriented lights.
Measuring lumens is hard because you need a way to collect all the light, or at least average it, then put that average on a sensor. Commercial integrating spheres for this purpose cost thousands of dollars. It's possible to estimate using a shoebox and a smartphone though, assuming you have a light source of known output with which to calibrate it. I wrote an app for that: https://github.com/zakwilson/ceilingbounce/ https://github.com/zakwilson/ceilingbounce/
- mehrdadn 9y agoThat's awesome info, thank you! :)
- Zak 9y agoI should also mention that a lot of reviews of flashlights found on Amazon praising things I would rate as absolute junk are probably entirely honest. If your last flashlight used alkaline batteries and an ancient LED, or even an incandescent, anything using an LED from this decade and a Li-ion battery is going to look pretty impressive. That Li-ion cell might well be taken from a laptop battery sent in for recycling, and the charger it comes with might burn your house down, but it's still impressive to the average person. On the other hand, I've seen a one-star review for not including a battery. It never said, or even suggested that a battery might possibly be included. My conclusion is that Amazon reviews for most kinds of products aren't useful for much more than determining if a product has an unreasonably high failure rate.
- mehrdadn 9y agoYeah, I definitely did find these impressive for the same reasons you mention... hopefully my house won't burn down with the charger I got (it hasn't yet)!
- Zak 9y agoJust make sure it's not this one: http://lygte-info.dk/review/Review%20Charger%20Bowei%20HC-103W%20UK.html http://lygte-info.dk/review/Review%20Charger%20Bowei%20HC-10... And ideally, see if you can find your charger tested here: http://www.lygte-info.dk/info/indexBatteriesAndChargers%20UK.html http://www.lygte-info.dk/info/indexBatteriesAndChargers%20UK... If it is the first one, break it so nobody else finds it and tries to use it, throw it away and replace it. The Xtar MC1 is the cheapest safe charger commonly sold in the US; they're about $5.
- mehrdadn 9y agoHaha, thank you for the heads up :) my charger is not on that list apparently... it's this one (which is no longer being sold; sorry for the low-res image): https://imgur.com/VpPNswX https://imgur.com/VpPNswX But some of the batteries are on there with not-great reviews... I guess I might have to replace them?
- Zak 9y agoYeah, those batteries are junk. Try the Sanyo NCR18650GA from illumn.com.