Ra Clicky lumens vs. surefire lumens

Viking

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Does anyone know if Ra Clicky/HDS is honest about the lumens output , like surefire is.

Is it measered from the same distance?
 

Brasso

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In fact HDS calibrates each individual light to put out the specified lumens.
 

precisionworks

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The test of any light is the light's reading in an integrating sphere. Every SF I've tested in my shop built sphere reads at least as much as claimed, usually more (see Building an Integrating Sphere ... in the General Light Discussion forum).

I tested a U2 last night, latest model, at 161 lumens. SF claims 100 :)
 

abarth_1200

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"HDS Systems is the only flashlight manufacturer that measures the output of each flashlight after it is completely assembled and adjusts the output of each flashlight so each flashlight will produce the specified output."

Taken from the FAQ's at HDS Systems
 

precisionworks

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Is it measered from the same distance?
integratingsphere.jpg


With an integrating sphere, like the example above, the "distance" is not an issue. Spheres are calibrated using a known standard lumen light source, driven by a closely regulated power supply. Whether the sphere is 12" or 12' makes no difference, as both sizes will read exactly the same lumen output from the same flashlight.

The theory behind an IS is:

Integrating spheres are designed to achieve homogenous distribution of optical radiation by means of multiple Lambertian reflections at the sphere's inner surface.
Couldn't have said that any better :nana:

been after a U2 for a few years. I might look into buying one now.
The U2 is still one of my favorite SF models, even after years of buying, selling & using many lights more costly than the U2. Because of the "turbo" head, beam distribution is beautiful. And the range of output is broad. On top of all that, the UI is dead simple - twist the collar to go either brighter or dimmer.

Not the Latest & Greatest, but one of the best that SF has ever made.
 
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DM51

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HDS gives accurate measurements.

Surefire's measurements vary according to whether they are incan or LED, but to remain on the safe side they NEVER exaggerate the figures. That means the output of a SF light is usually significantly understated - a SF light will output more light than stated on the box.
 

Viking

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Thanks.
I guess that means a SF LX2 rated to 200 lumens , probably will output more light than a RA Clicky also rated to 200 lumens , because Surfire underplay there lumens claims , and HDS do not.
 

jh333233

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yes HDS is very honest. its only the Chinese companies that artificially inflate lumen ratings.
Couldn't agree more, most ****fire overrate their lumens, they mark the "maximum possible lumens achievable by the led itself" but not the light
 

gswitter

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Thanks.
I guess that means a SF LX2 rated to 200 lumens , probably will output more light than a RA Clicky also rated to 200 lumens , because Surfire underplay there lumens claims , and HDS do not.
Not necessarily. And the beam profiles of these two are very different, so it's tough to compare them in anything other than an integrating sphere.
 

pjandyho

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Thanks.
I guess that means a SF LX2 rated to 200 lumens , probably will output more light than a RA Clicky also rated to 200 lumens , because Surfire underplay there lumens claims , and HDS do not.

There is a difference between lumen and lux. Lumen measure the total light output whereas lux represents the intensity of the light of the hot spot falling on a surface area. A laser has a very intense lux number but is impractical as an illumination tool. A flood light has a very low lux but it makes a very good illumination device for general close up application. It all depends on what you want your light to do.

Surefire uses a TIR lens instead of a reflector in the LX2. The TIR lens helps focus all the light forward for maximum throw and has very minimal side spill. While the LX2's narrow beam profile is still useable for close up applications, I much prefer the more floody HDS 200 lumen rotary for 90% of the times when I needed a light, because most of the time when I needed light it would be for up close usage. I find both HDS and Surefire to compliment each other very well.

So, lumen alone does not tell you how bright the light would be for a certain application. Knowing the light's intensity and beam profile is more important.
 

mrlysle

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There is a difference between lumen and lux. Lumen measure the total light output whereas lux represents the intensity of the light of the hot spot falling on a surface area. A laser has a very intense lux number but is impractical as an illumination tool. A flood light has a very low lux but it makes a very good illumination device for general close up application. It all depends on what you want your light to do.

Surefire uses a TIR lens instead of a reflector in the LX2. The TIR lens helps focus all the light forward for maximum throw and has very minimal side spill. While the LX2's narrow beam profile is still useable for close up applications, I much prefer the more floody HDS 200 lumen rotary for 90% of the times when I needed a light, because most of the time when I needed light it would be for up close usage. I find both HDS and Surefire to compliment each other very well.

So, lumen alone does not tell you how bright the light would be for a certain application. Knowing the light's intensity and beam profile is more important.

+1. Well said. It's hard to find one tool that does all things well. Usually where a tool will excel at one thing, it falls short in a different area. That being said, I didn't buy any of my HDS lights to be "throwers". But for general use, mostly close up illumination tasks, they fill the bill. Either Surefire or HDS will make a light that's at least as bright as advertised, and will fulfill your requirements. You just have to pick the right model for what you want to accomplish. But the OP's original question? 200 lumens is 200 lumens. Doesn't matter whos name is on the lumen generator! :)
 
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