Beam Pattern.

shahzh

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May 8, 2008
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I'm quite new into this.....I tried searching but couldn't find the answer. My question is, I just got my new Jetbeam Jet III Pro and I just notice that the center beam (hotspot?) is not really center with the nearest outer ring (at about 3 feet). Same goes with my Jetbeam CL-E V2. Is this normal?

I also noticed that some of the Jetbeam (ie: Jet I Pro) beamshots from the other review threads also shows the same thing. I'm really curious to know since I'm new at this.:confused:
 

Zenster

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Oct 29, 2007
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Texas
Lot's of lights, even some of those considered to be among the best, often have beams that are not perfectly centered.

The question is; are you using the light to watch the beam, or are you using the light to be able to see what it illuminates?

White wall beam watchers are pretty anal about their beams because the beam is what it's all about.
On the other hand, people who use lights to light up things they want to see might not even know what you're talking about when you mention "off center beam" because they're not looking at the beam, they're looking at the "stuff" that the beam is illuminating.

Of the over 30 lights I have, I couldn't tell you which are perfectly centered, or not, to save my life.
I turn on light. I see things. All is good. :twothumbs

:welcome:
 

shahzh

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Thats a good one. You're right. Thanks for the feedback it makes me feel much better now:wave:.
 

Yapo

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Yeah in practical use u dont really notice it much...especially in outdoor use. Its hard to have a perfect beam as a fraction of a mm or degree when positioning the LED will affect the beam.
 

Rob187

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Feb 26, 2006
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An off centre beam caused by flawed positioning of LED in reflector or fault in the reflector itself. More likely to be the former.

My Jet III's beam is symmetrical but shows the typical Cree beam, great hotspot with a somewhat yellow ringy halo. Not bad but not 'perfect' either.

I wouldn't describe myself as a white wall hunter but I definitely prefer a smooth even beam. An uneven beam (ignoring the rings) is not what the designer of the light set out to achieve. It is a manufacturing fault. Whether you consider it a sufficient reason to be unhappy with the light and return or sell it is up to you.

We all survived the dark with incandescent lights that had terrible uneven beams before these you-beaut LEDs came along...
 

shahzh

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May 8, 2008
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The beam is smooth and definitely in the center, the yellow ring halo is not, thats what bugging me :sigh:. But overall I'm happy with the Jet III Pro performance :twothumbs.
 

Yoda4561

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Jan 22, 2007
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Florida, U.S.A.
Depending on how picky you are almost all lights will have beam defects. Even the famous surefire incandecent lamps are not always as pretty as some folks want them to be. Small variances in lamp/reflector positioning make a big difference in the beam and manufacturers do they best they can (at least the good ones do). Inova's first run of Radiant AA lights had a reflector that had a machining defect of .0005 inches. This resulted in a huge donut hole at all distances in the beam.

My Malkoff M60 is so very close to perfect, but the hotspot corona is slightly oblong, took me a week to notice even though I keep shining it on a white wall waiting for it to get brighter for me. My surefire M3 when I had it had a football shaped beam, this is what they considered normal and was optimized for the best throw with their lamps.
 
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