Questions/discussion regarding the focus feature of a LED based flashlight

Zflashlight

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As i'm new to the whole flashlight discussion, and severely limited when it comes to electronics, optics and so on, please correct me when i'm wrong.
And i don't own a Led Lenser, so i'm basing my assumptions on a flashlight i have that i think uses the same main principles when it comes to the focus feature.

As i see it, the Minimag AA incan can "focus" because the bulb is elevated relative to the bottom of the reflector. When i turn it on, it produces a floody beam (or i would if he bulb produced light evenly), because it's closer to the lens, having a bigger angle to light. Light still hits the reflector, but not as much as when i unscrew the head.
As i unscrew the head, the head moves out and the bulb's relative position is lower. When it is at the lowest position (but still lighting forward and to the reflector, not behind it), it becomes 'throwy', since more light is hitting the reflector and going 'straight' out.

Compared to a Minimag LED, the difference becomes obvious. The LED is already at the bottom before i even turn it on. The reflector is different probably to compensate this fact, having a bigger hole, but obviously doesn't mimic the original Minimag incan effect.

From this my question is:
Is it impossible to raise the LED to a position closer to the incan one?
If yes, or just difficult, is it because of heat-sinking, circuit attached to the LED, both?

I'm thinking that this is probably why Led Lensers and the like use an aspherical lens - an actual lens rather than just something protecting the led/bulb. A standard reflector would block too much light.
Like using a magnifying glass in front of a normal flashlight, the light is focused to a smaller area, producing more light in said area. Moving the magnifying glass farther or closer changes the focus.
The thing is, everything around it is dark, there is no visible spill at all, an all or nothing kind of thing.

A Maglite like flashlight, if possible, would produce a more balanced light, because even when focused it still produces usable spill.
Which is mainly why i'm interested to know more about this.

I hope some of you can help me understand this a bit better.
 
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mcnair55

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I look forward to your replies,I have a couple or three focus type lights must admit I am not keen on them,rather select a light from my collection for the job I want a light for(an excuse to play with a different type I think I am saying).:D
 

jellydonut

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It is possible to raise the LED. I don't know how the LED Lensers do it, but many modules that convert incandescent lights to LED use what is called a 'tower module' in order to get the LED leveled at the same point as the filament in the bulb it is replacing. It's called a tower module precisely because the LED is raised on a piece of copper or aluminium, like a little tower. Also, many full-size Mag LED conversions retain the 'focusing feature' of the light with an LED. I have one of these and I find it is just as useless as it is with the stock Mag. There's one single position where the beam is focused, and with the rest it is a defocused blotchy useless mess.

In my opinion, and of course an opinion is like a bottom, everyone has one and they pretty much all stink, but..

Having an adjustable focus is not a feature; it's a bug. They say 'our flashlights are focusable'. What it really means is 'we cut corners by not focusing our flashlights from the factory and leaving this job to the user'.

What I would get instead is a flashlight with a properly focused, somewhat throwy beam.. And then get a diffuser for it for those situations where you need flood. This way instead of having a defocused, artifacted, blotchy 'flood' (more like 'mess') beam for upclose and a subpar throw beam, you'll have the best of both worlds. Perfectly balanced throw beam with a good hotspot, and a smooth, wide degree flood without artifacts with the diffuser filter.

But to each his own of course. :nana:
 

Zflashlight

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It is possible to raise the LED. I don't know how the LED Lensers do it, but many modules that convert incandescent lights to LED use what is called a 'tower module' in order to get the LED leveled at the same point as the filament in the bulb it is replacing. It's called a tower module precisely because the LED is raised on a piece of copper or aluminium, like a little tower. Also, many full-size Mag LED conversions retain the 'focusing feature' of the light with an LED. I have one of these and I find it is just as useless as it is with the stock Mag. There's one single position where the beam is focused, and with the rest it is a defocused blotchy useless mess.
I have one of the Niteize dropins, and i think it's not raised at all, or just barely.
When unscrewing the head, and just when the light turns on, it's practically on throw mode if you will.
Continuing to unscrew the head, the LED goes into 'teh tunnel o'death', where it's actually losing light (the reflector supplied by Niteize ends in a tunnel shape). The beam pattern turns into what you observe as blotchy.
It's never on a floody position.

Having an adjustable focus is not a feature; it's a bug. They say 'our flashlights are focusable'. What it really means is 'we cut corners by not focusing our flashlights from the factory and leaving this job to the user'.
I respect your opinion, but i think the maglite, if it had a proper light source, would change your opinion. Or not :D
What I would get instead is a flashlight with a properly focused, somewhat throwy beam.. And then get a diffuser for it for those situations where you need flood. This way instead of having a defocused, artifacted, blotchy 'flood' (more like 'mess') beam for upclose and a subpar throw beam, you'll have the best of both worlds. Perfectly balanced throw beam with a good hotspot, and a smooth, wide degree flood without artifacts with the diffuser filter.
It is indeed what i think is the practical buy option, but i still want to know more about this.

Cheers
 

jellydonut

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I have a Maglite 2C with a Malkoff dropin, I think that's about as proper as it gets, don't you? :eek: I always keep it in the focused, tight hotspot position. Defocusing the beam by twisting the bezel several turns is just a hassle, not to mention finding back to the 'magic' focus spot.
 

Zflashlight

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Oh i see. I don't have a regular Maglite, only minis.
A MM is fast enough i think to focus. You don't turn that much.
 
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