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Flashlights - how to check lumens?
Posted: Tue Dec 14, 2010 12:54 pm
by essdee1972
Hi, All,
I am in the process of getting a Cree flashlight through someone in US. He says they have 1200 lumen models for approx 70-80 USD. I wanted to know if (and how) one can estimate the lumens in normal urban scenario, without lab kind of facilities.
Would be grateful for any info.
Thanks,
EssDee
Re: Flashlights - how to check lumens?
Posted: Tue Dec 14, 2010 2:54 pm
by Rajat
Not possible without a "light"meter or an instrument called an Integrating Sphere. Just rely on the declaration by a reputed manufacturer.
I doubt if you will be able to get a LEd flashlight with an output of 1200 lumens for $ 70-80.
They do have models with a 1200 lumen output but these are expensive and very few led flashlights in this category are available at present. More commonly you have the HID's with this kind of output or even more.
Re: Flashlights - how to check lumens?
Posted: Tue Dec 14, 2010 4:46 pm
by Subal das
http://szobm.cn/product/359287879-20027 ... light.html
here is 1300LM for usd 75
these company making a lot of more lights and mounts also
-- Tue Dec 14, 2010 6:01 pm --
one more powerful light UltraFire RL-2088 OSRAM LED 1200 Lumen
http://szobm.cn/product/338834406-20027 ... ights.html
Re: Flashlights - how to check lumens?
Posted: Tue Dec 14, 2010 6:55 pm
by Rajat
Most Chinese companies are known to inflate their lumen ratings to make people feel good about it. An ordinary person can not check the out put because the meters to measure the lumen output are quite expensive. No reputed manufacturer ever does it and most do not even claim to make flashlights with a 1200 lumen output.
What these Chinese manufacturers do is that they quote the lumen output of the LED at its maximum in test conditions and NOT of the output of the LED when it is IN the flashlight.
Secondly the LEDS that they use are not single LEDS but multiple chips in a single bulb like Quad cores and even 6 chips in the Ultrafire OSRAM LED 1200 which Subal has brought up above. There are focusing problems then. The result is that you do not get enough "throw" in the beam or it does not travel a good distance.
Lumens is the total light output of light coming from the source and not the brightness of the light at the most intense point.
Secondly there is much more to a flashlight with this type of output other than just a 1200 Lumens LED. Look up "Heat Sinks / heat management" and circuitry to handle it and you will know what I mean.
These is a reason why the good manufacturers around the world do not offer such products or make such claims and if they do they charge you for it because they back up the products with lifetime or multiple year guarantees.
Please look up any such product from a manufacturer of repute.
Re: Flashlights - how to check lumens?
Posted: Tue Dec 14, 2010 8:11 pm
by Subal das
that is all understandable, but what I have seen many times in fact western manufacturers trying to justify their high price by good quality and that is very often fake claim, as their goods made in China too.
question is to find balance between acceptable price and quality.
what would you say about that one Rajat.
900L (suppose) why not to try for $30
http://szobm.cn/product/345163565-20027 ... light.html
Re: Flashlights - how to check lumens?
Posted: Wed Dec 15, 2010 10:36 am
by essdee1972
Thanks, Guys!
Re: Flashlights - how to check lumens?
Posted: Wed Dec 15, 2010 3:26 pm
by Rajat
Subal das wrote:that is all understandable, but what I have seen many times in fact western manufacturers trying to justify their high price by good quality and that is very often fake claim, as their goods made in China too.
question is to find balance between acceptable price and quality.
what would you say about that one Rajat.
900L (suppose) why not to try for $30
http://szobm.cn/product/345163565-20027 ... light.html
In law suit happy western countries not to specially mention the U.S. of A no manufacturer will risk faking the specifications of "tactical" products. These flashlights come under the "tactical" category and the risk will not be worth taking for any good and known manufacturer.
Overpriced: Yes I agree but this is attributed to intensive marketing, lifetime warranties and the made in Europe or US tags. Do not buy the made in the West products, you can buy the made in China products from these companies as even the Chinese products that they make are made under their specifications and control.
OR if you have noted the very same companies also sell equivalent products for a lower price to churn out volumes of that item. Examples are available.
To find a balance between acceptable price and quality is the right way. I agree with this but your example of a $30 900lumen flashlight does not justify this.
Neither does your buying a 5.11 karambit made with S 30V or a Ka bar. You could easily have bought cheap not so known Chinese knives with some "great" specifications for less than half the price. Then why the 5.11 or a Kabar.
Re: Flashlights - how to check lumens?
Posted: Wed Dec 15, 2010 5:31 pm
by Subal das
thanks Rajat you are very helpful as always.
lights is not so important for me, as knives, but my karambit and kabar actually made in taiwan and not overpriced.
what would be you opinion of good quality light: rechargeable, with good beam of light up to 100m
Re: Flashlights - how to check lumens?
Posted: Thu Dec 16, 2010 3:08 pm
by Rajat
Subal das wrote: but my karambit and kabar actually made in taiwan and not overpriced.
Like I said above: you can buy the made in China products from these companies as even the Chinese products that they make are made under their specifications and control.
This was with reference to the price and quality combination.
what would be you opinion of good quality light: rechargeable, with good beam of light up to 100m
A very basic but great example will be the Olight T 25 at $ 44
See:
http://www.batteryjunction.com/t25-olig ... light.html
This is rechargeable in the sense that it uses 2 x AA batteries and you can buy rechargeable AA's anywhere in India.
Most of the the other CR123 flashlights accommodate rechargeable 18650 batteries and so these can be called rechargeable too.
Re: Flashlights - how to check lumens?
Posted: Thu Dec 16, 2010 7:10 pm
by mundaire
How about this -
http://tinyurl.com/23oauca ? Besides the output the feature I really liked was that it can convert from using a single CR123 to using 2xAA - a really neat idea IMHO!
The listed price is just 500 Rupees (including postage to anywhere in the world)!
Would be amazing if they can actually deliver what they claim within that price point!!!
Re: Flashlights - how to check lumens?
Posted: Thu Dec 16, 2010 9:52 pm
by Subal das
batteryjunction.com do not have India in their country shipping list, I sent request let see if they ship to India or not, few others US based sellers from Ebay did not ship to India.
sent email to this Chines guy GoMarketStore also, thanks mundaire
seems likes time when were getting lights form electric hardware stores are gone. by the way I have seen recently few lights in Himalaya book store here in Hyderabad, just phenomenal ... beam up to 1500m with 60 lumens.
Re: Flashlights - how to check lumens?
Posted: Fri Dec 17, 2010 1:32 pm
by Rajat
Subal das wrote:batteryjunction.com do not have India in their country shipping list, I sent request let see if they ship to India or not, few others US based sellers from Ebay did not ship to India.
Subal, the link was just so you could see the model. You will have to look up a store that ships to India. At Ebay a lot of Hong Kong sellers ship to India.
Flashlights with extension tubes are common and have been on the market for a long time. However mostly these are to increase the voltage and therefore the output and run time by adding more batteries of the same type. In this case you are able to substitute 1 x Cr123 which is 3 V with 2 x AA of 1.5 Volts each. The result: it will be economical as CR123A's cost more but the batteries will rattle in the tube as the diameter of the CR123 is more than the AA. The spring will reduce it but not eliminate it.
The rating of 500 Lumens is surely exaggerated @ 3 Volts. Most good flashlighst do not claim more than 220-250 Lumens at this power input.
However I may be wrong and at Rs 500 you do not have much to loose.
by the way I have seen recently few lights in Himalaya book store here in Hyderabad, just phenomenal ... beam up to 1500m with 60 lumens.
Sorry I could not help it! Beam up to 1.5 Kilometers with 60 Lumens. I do not know what to say.
Maybe they mean to say that someone at the other end can see the source of the light from 1.5 Kms away. The beam cannot travel and light up something at a distance of 1.5 Kms @ 60 Lumens and this is what is usually meant in the flashaholic vocabulary when you say up to 100m or 1000m etc.
Re: Flashlights - how to check lumens?
Posted: Fri Dec 17, 2010 2:23 pm
by essdee1972
Thanks, Mundaire! That guy sure has an amazing range... I think I will order a low price item (500 bucks or so) and see whether he can deliver the goods! Will let people know if he does....
Cheers!
Re: Flashlights - how to check lumens?
Posted: Fri Dec 17, 2010 2:46 pm
by Rajat
For a truly enlightening experience go for a HID from the same guy. I do not know how the overall quality of the product will be but if decide to buy it you will never use an ordinary flashlight again
http://cgi.ebay.com/35W-Xenon-HID-Recha ... 4699wt_905
Re: Flashlights - how to check lumens?
Posted: Fri Dec 17, 2010 11:55 pm
by Subal das
that will qualify as assassin's flush light, scary thing to switch on, what would people say
scopeandlaser.com communicating first from the whole bench of lights guys I contacted previously