This 9P beam normal?

logicnerd411

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Just got my 9P (thanks dano!) and turned it on. WHOO! Bright! But it looked funky:

9P-beam.jpg

(Image balance set incorrectly due to user stupidity. Just got the camera this morning... /ubbthreads/images/graemlins/grin.gif)

It's an oval like shape. Weird? Not weird? Set me straight. Thanks in advance...

Dan
 

lemlux

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logicnerd:

That's a particularly good one! Your hotspot is round. My P90's are more elliptical than yours.
 

FalconFX

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Normal? Not sure... Although my D3 Defender has that similar shape in its beam... It's not exactly circular, like the N2 in an SRTH is...
 

CM

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logicnerd,

I have two P90's with oval hotspots. I got one replaced by Surefire (should have had both replaced) and the replacement, though improved, is still oval-ish. I've given up and conceded to the oval beams as being a "feature" of the P90's. Funny, I have a P91 with a pretty symmetrical beam, but it may be that it's so bright I really can't see the imperfection, just a big bright blob of light.

CM
 

Experiment_626

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Your beam shot looks very similar to my 9Z using either the P90 or P91 bulb assemblies. I agree with CM that the P91's seem to be somewhat less oval shaped, but not perfect.

However, I did look at the alignment of the filament in relation to the ends of the oval hotspot, and they line up with each other perfectly. So, since I have had similar results with the 4-5 P90's and both P91's over the last four years of carrying the light, I would say it is to be expected.

Surefire still makes the best flashlights hands-down in my opinion.
 

Size15's

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The shape is likely due to the shape and type of filament and the reflector.
long/curved filaments do not have as round a beam as shorter, straight filaments.
The reflectors are able to collect much of the light very close to the bulb which mean the beam is shaped much like the filament.

At least that's how I think it works.

Al
 

dano

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Cool...it made it before the Sunday extra day wait layover.

Of the three 3-cell SF's I still have, all three have an ovalish beam. The P91 lamps are even more oval.

I guess it''s a filament issue...

--dan
 

Experiment_626

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I agree with Size15s, which would make this a result of design, so to answer logicnerd411's original question, I believe it is normal behavior.

If you really want to see bright light from your 9P, pick up a P91 bulb assembly (around $25). You will be even more impressed with the output than with the stock P90, but the downside is that you only get about 20 minutes of run time rather than the 60 minutes or so with the stock bulb.
 

llvo

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my P90 is oval(just like yours)
my P91 is 'V'-shaped oval /ubbthreads/images/graemlins/rolleyes.gif (too hard to describe?)
my KL3 is prefectly round

I like the output of the P91<--that's what a D3 Defender's output should be while I like the KL3 for the reliability and long runtime.
 

Blikbok

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All of my 9v lights have oval beams. The higher output lamps seem rounder, but I think that's because my eyes can't distinguish the shape of the stronger beam.
 
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