Behemoth Tactical Lego Shootout Summer 09...

[Sgt. LED]

This is going to be illuminating.

 

[mdocod]

I've been chatting on the phone with a good friend here on CPF about a way to do a sort of "standardized" beam-shot or at least, something that anyone could go out and replicate. Like a printable target on a piece of paper, then plated at such a range... With larger size targets placed at greater ranges (proportionally with distance) to help decipher the difference in target illumination down range of different lamps.

Also, I just got a LuxMeter in my new multi-meter. I'm thinking I could do some sort of test routine to calculate maximum effective useful range of various configurations based on needing to achieve some minimum lux value at a particular range. I will need to establish some baseline minimums and will need some input to make those decisions.

What do you think?

-Eric

 

[Outdoors Fanatic]

BRING IT!!!!!!!!!!!!!
:thumbsup:

 

[Tony Hanna]

 

[FrogmanM]

With your help Eric, this may be the summer I pick up a few SF Incans.

I look forward to the upcoming shootout.

-Mayo

 

[Outdoors Fanatic]

This summer we are all going to be :laughing:

 

[Blacksidesniper]

I've been chatting on the phone with a good friend here on CPF about a way to do a sort of "standardized" beam-shot

Sounds good.

 

[mdocod]

I've made some updates

 

[Outdoors Fanatic]

I've made some updates

Thanks man! Really impressive work here...

 

[SolarMan]

Thanks Again for doing all the homework for us!

 

[Justin Case]

The popular 11836 D26 R2 drop-in ("super bright" ~1A drive)

(On 2x3.7V li-ion cells)
peak lux @~1M: ~6000
central beam angle: ~8°
spill beam angle: ~60°

(On 1x3.7V 18650)
peak lux @~1M: ~4300 (LiCo cell at ~4.10V resting)
central beam angle: ~8°
spill beam angle: ~60°

Comments: throwing this in for the sake of comparison so folks can see how a few LEDs compare to the world of tactical incans. I have to say though, that dollar for dollar, the 11836 continues to be, IMO, one of those true gems in the rough. I own several, no failures, great performance on a wide array of power sources (even 1 li-ion cell works plenty well for general use here). Can't beat the el-cheapo-ultra price tag here. I was especially surprised to find that my original guesstimates of output on a single li-ion cell were low, it's producing an estimated 140 torch lumen on a near-full-charged 18650. Slight cree ring is noticeable on white walls, in normal use it is not a significant issue, transition from spot to spill is softened properly.

I personally can't recommend the current version of the DX11836, unless you mod it to use a different driver. See this thread.

 

[Outdoors Fanatic]

Where are the beamshots??

 

[Patriot]

All excellent info MD!

Others seemed to be referring to pictures that I was unable to see. Is there more than just the first picture of the assemblies?

 

[mdocod]

Hi Justin Case,

On the 11836, they must have changed the driver since I got mine many months ago. Mine consume almost exactly 4W, with a regulated cut-in voltage of ~4.5V +/- 0.1V it would seem. The driver efficiency drops off slightly with higher input voltages, like 4xli-ion cells, but nothing as severe as you measured, and the heat generated is very reasonable. No more than my LF brand drop-ins. On a single li-ion cell, mine start off ~140 lumen, and diminish to ~50 lumen through a discharge, and can be run like that in an all-plastic host non-stop without over-heating problems.

-----
Hi Outdoors Fanatic and Patriot

Pictures are coming, I am working on a new way of doing beam-shots that will help really show the beam characteristics and usefulness at range. I am planning on a combination of upwards of 3-4 beam shots per lamp assembly. Each beam shot will help portray something different...

One thing I am working on, is a way to take a "white-wall" beam shot, and make exposure adjustments and post-processing adjustments, not for the purpose of any sort of brightness comparison, but to define the beam shape, size, spill, and transition to spill. Ideally, if I can get this to work the way I want to, only the very brightest part of the beam will appear fully-edging-on-over-exposed.

See, there are big variations in the way that different lamps and reflectors work to produce beams. The "lux" figures above combined with a rough measurement of beam width are useful to a point, but are a bit mis-leading when you consider that some lamps produce a lot of lux throughout the central beam (like on 2.5" turbo-heads mostly), while others produce a peak lux at the center that handily competes with the 2.5" turbohead, but with a softer wider transition to spill. After using lamps like the HO-13 and EO-13, I personally can't find much use for a 2.5" turbohead anymore because the wider softer transition is actually preferable (to me) now that I have compared side by side.

I am also going to do some experimentation and research, and figure out how much lux is needed at range to accurately identify things. Each lamp assembly will then be assigned a "range" capability rating for use in different scenarios. Different applications require different levels of illumination. So a wide range will be assigned as the "maximum range" depending on the application. (for example, seeing movement off in the woods can be done with a few lux more than likely, whereas making accurate friend/foe identifications requires much more light). I am thinking that more than likely I'll do a set of 2-3 beam shots each at a different range using some sort of common target or collection of targets.

It's going to be a lot of work, but I think it will be a neat resource when all said and done.

 

[Justin Case]

Hi Justin Case,

On the 11836, they must have changed the driver since I got mine many months ago. Mine consume almost exactly 4W, with a regulated cut-in voltage of ~4.5V +/- 0.1V it would seem. The driver efficiency drops off slightly with higher input voltages, like 4xli-ion cells, but nothing as severe as you measured, and the heat generated is very reasonable. No more than my LF brand drop-ins. On a single li-ion cell, mine start off ~140 lumen, and diminish to ~50 lumen through a discharge, and can be run like that in an all-plastic host non-stop without over-heating problems.

DX definitely changed the DX11836's driver. It used to be green and be the same one as in the DX6090. It was PT4105-based. Now the driver is blue and it is YB1682-based.

My old DX11836s, using the same driver as for the DX6090, performed very well when tested on my bench supply. Not so the newer ones (with the new driver) that I've gotten within the past few months.

 

[maxspeeds]

Looking foward to the beamshots

 

[Patriot]

Thanks MD. No rush on the pics, I just thought perhaps my browser was acting up. I'm very much looking forward to your shots!

 

[mdocod]

update:
Added at least a dozen more lamps and re-did all of the lamp tests with a different arrangement and positioning that I think produced more accurate results for lux data. Comments have been modified. some "white-wall" beam shots have been taken at various exposures to show beam characteristics and will be posted hopefully in the next 48 hours.

 

[Outdoors Fanatic]

update:
Added at least a dozen more lamps and re-did all of the lamp tests with a different arrangement and positioning that I think produced more accurate results for lux data. Comments have been modified. some "white-wall" beam shots have been taken at various exposures to show beam characteristics and will be posted hopefully in the next 48 hours.

Thanks Eric!

 

[mdocod]

more updates