surefire a2 incandescent beam question

hello
i am quite disappointed with my a2...
while the led beam is ok (maybe to narrow but thats opinion) the corona shaped sidespill of the incandescent seems to waste a lot of light
maybe i am a litte mean but i expect a flashlight of this price to be flawless
my question is plainly if this is normal
thank you

my first beamshot /ubbthreads/images/graemlins/wink.gif

its normal...its speculated that the double brightness corona is caused by the partially frosted bulb of the A2. so long as the main beam itself is in focus your light is normal /ubbthreads/images/graemlins/smile.gif

mine looks the same.
I think that's the price for a (relatively) thight focus from a small reflector

jones,
Welcome to CPF!
IMHO your A2 will grow on you once you get used to the tailcap and how you carry an deploy it. You might find Quickbeams review interesting.
http://flashlightreviews2.home.att.net/reviews/surefire_a2.htm

hello
thank your for your answers!
i think will sell my a2 when the ls4 is out and get an additional "high power" light (sf l6 looks nice)
until then the a2 is still the first flashlight that showed me there is something else than maglite /ubbthreads/images/graemlins/wink.gif

[ QUOTE ]
i expect a flashlight of this price to be flawless

[/ QUOTE ]

All things are relative, and nothing is flawless. What you may consider to be the "perfect" light may not be what the engineers who designed the A2 consider to be the "perfect" light. You need to find what works best for your situation.

The spillbeam is very important. Look at my review of the Inova X1 for a light with no spillbeam. It's useless in most practical situations.

For what it is, and what it does, the A2 is IMHO currently the best you're going to find. /ubbthreads/images/graemlins/thumbsup.gif

hi quickbeam

sure there is not the one perfect light
but i think that a light with two beams has no need for sidespill at the higher power level
and as the light was originally designed for aviation use (guess what /ubbthreads/images/graemlins/wink.gif) the sidespill of the incandescent beam has absolutely no purpose since there is only need for one bright spot to check your equitment from the ground

dont get me wrong - the a2 is a good light (especially if you havent seen a good light before as i did)
i guess i just expected to much
or it is a excuse for myself for buying more flashlights /ubbthreads/images/graemlins/smile.gif

btw: there are many other good pages but i like the reviews on yours the best!

jones: not to worry...i've occasionally been disappointed with lights that were otherwise fine due to over-expectations. the A2 is actually one of my most used and carried lights, simply because it is so versatile. if you weren't a flashaholic i suspect the A2 would be one of the few flashlights you'd ever need (besides an arc AAA or AA) /ubbthreads/images/graemlins/wink.gif

Yep, for $160 I would expect better... After all, if this was a Streamlight Product you'd beat this beamspot issue into the ground! Wouldn't ya? /ubbthreads/images/graemlins/grin.gif

Try $119 at:
http://botachtactical.com/sua2avfl.html

I have two A2's, a red and white (different applications). I think these are just about the most versatile light out there. Great product.

I also find the slight sidespill on the A2 to be just fine. The vasts majority of the light goes into the center spot for throw - just what i need, but the slight sidespill is great for that extra peripheral detail.

j

Yep, that's the typical shitty beam of the A2. It sucks, doesn't it. It's due to the frosting on the tip of the lamp.

Whats the purpose of the frosting?

I just bought the a2 and I think it is one of the best lights I own.

Boy, I just used my A2 on a 10 day long sailing trip. I have to tell you its just about the best light I have ever owned. The only thing that would improve this light is if they came up with a long throw LED to replace the incandescent - but that is a bit of a tech advance ahead yet.

I liked the A2 I have (white leds) so much that I bought a red LED one too.

So, no - I don't think it has a bad beam. Quite a good one on the contrary.

j

I think side spills are actually necessary, otherwise in pitch dark environment you'll have trouble. That's my experience from camping: using a Maglite when camping, with the beam set to the tightest, everything else not in the beam range could hurt you (as it's too dark for everything except what you intended to see). You shouldn't focus on the target alone. So I would say, we normal people do not have any legitimate reason to have a beam without any side spill, because side spill saves us.

The only 2 situations you want to have no side spill are when you want to pinpoint something in a long long distance (so you need a super tight beam without any side spill to have a real long throw, like turboheads do), and when you do not want to reveal your location in darkness. Both are special tactical situations (although for long throw, hunters may need it too). Even when in real tactical situations, you still want to have side spills even though you have a tight beam (for LEO's, that's to make sure they don't shoot the wrong guy, directed the beam to enemy's face or not).

And for aviators, do you actually think they can check the equipments without side spill? Think about it: seeing the big pictures is always the best way to locate errors; if you have a no side spill beam, how can they make sure every little part is checked? You may miss some; that's the whole point for side spill: not to miss anything important which isn't in our target range. So I would say, if A2 has no side spill, then it will not qualify as a light for aviators.

Therefore, Surefire's lights, except the KT turbohead series, are designed to HAVE side spills. KT conversion kits are designed to have no or little side spills for long throw, although many reviews in CPF said they're not too good. And I believe except Inova X1, no lights will actually not reveal your position.

That said, if you want to have a light with absolutely no side spill, that's a little extraordinary, and I think only the streamlight TL series may be able to do that, if you don't want to go for turboheads.

Mind you, though, L4 is designed to be very flood, it cannot throw far. So for something that A2 can shine from a certain distance, L4 will not do any good. I think, for aviation purpose, L4 cannot perform well.

Just my $.02

i think that we all too often fall into the trap of examining beam shapes up close on walls where the A2 does look rather poor!

however, in real world use its beam is excellent - a tight hot spot with impressive throw and functional sidespill too. i really like mine - no regrets on the purchase at all.

Bulb Frosting Improves SureFire A2 Beam

The source of the rings in the A2's spill is the part of the bulb that is unfrosted. The bulb envelope has varying thickness near the tip, and it acts as a lens which causes uneven light distribution (artifacts) in the spill. If you look at the bulb of the A2 while the light is on, you will be able to see the filament glowing, but only for a narrow range of angles from the center of the beam. It is in this range of angles that the bright outer ring occurs.

For angles closer to the center of the beam, the direct light from the filament is softened by the frosting that SureFire applies to the tip. For angles farther from the center of the beam, the direct light from the filament is hidden by the bezel. IMO, SureFire's intent was to eliminate all direct light from the filament – to filter it through the frosted section – in order avoid the lens action of the curvature in the bulb.

But SureFire (again, IMO) didn't extend the frosting enough, leaving that gap where the naked light can generate a huge ring around the hot spot. It is the same kind of ring that one finds in the E2+. In the E2+, a modified P61 lamp assembly is used in a modifies E2e bezel, giving 120 lumens. But the P61 LA also has a bulb with an irregular envelope, causing artifacts.

Another CPF member told me about his success in eliminating the rings by frosting the tip of the P61 bulb. I tried the same trick on the A2. It worked beautifully. What a difference!

I used the techniques and supplies discussed in the Frosted Glass Mod thread. I applied a thin ring of etching paste around the bulb at the base of the SureFure-frosted part, left it there for five minutes, and rinsed and cleaned carefully.

<font color="red">WARNING LABEL:</font> For those of you CPFers who want to try this, be aware that it's not that easy to do it safely. In addition to buying chemicals and supplies, a pretty large investment in safety is required – not only in equipment like rubber gloves, goggles, etc – but also in educating yourself about the dangers. The major etching ingredient is very nasty. It can be more dangerous than an explosion that might result from improperly charging naked Li-Ion batteries. Someone at my son's place of work who used this etching ingredient was very careless, ignoring multiple safety considerations. He didn't even wash up afterward. Long story short, he had to have the tip of his finger amputated. (If it sounds like I'm trying to scare you, you got the message.) Take care, and best of luck.

Paul

Re: Bulb Frosting Improves SureFire A2 Beam

bump

Re: Bulb Frosting Improves SureFire A2 Beam

You know what? If its that dangerous to deal with the frosting stuff, I think I'll just live with the rings. ;-o

J

Re: Bulb Frosting Improves SureFire A2 Beam

John,

Good approach. I know how you feel. It's wise to question how much of a disturbance the rings are to you.

Etching the bulbs is the way to go if you are curious about what will happen and are willing to read up on the dangers and ways to control them . . . and if you shine your light on the wall a lot (as I do). However, I lived with the rings in the beam for quite a long while. I found that, although the rings showed up starkly on the wall, when I was using the A2 to find my way or to inspect anything in the dark, I was completely unaware of them.

Paul