Luminus CFT-90 Testing - The Mother of all LEDs

I wouldn’t compare the numbers at the peak output. The inefficiency is indeed terrible. But at around 30A it’s much better in this regard (which doesn’t make it good actually). And it will still out-throw nearly anything on the market. And certainly anything close to its output.
I don’t see the point comparing it to XHP70.2. It’s much more powerful and efficient, but much bigger. XHP50.2 is much closer, actually pretty much the same size. And max output is close too, 5000 lumens with the dome. 50.2 leaks light to the sides, so it’s much less throwy with the same output. Efficiency? ~80W@5000 lm for XHP50.2 (with dome) and ~110W for CFT-90. Dedome and you’ll arrive somewhere in the 4000-4500 lm range with the same 80W consumption. Scale CFT-90 down to this level, it takes ~70W@4500 lm and ~60W@4000 lm.

The only thing I can see this LED being easily used in is a Big Aspherical Lens/ Fresnel build, can’t see a massive reflector with a massive aperture being cost effective.

$200.00 for LED/Driver with active cooling in an Aspherical Light with the cost of materials, machining and powering up to 40A….I don’t like aspheric lens lights, so it’s not attractive to me.

But I hope some one with some $$$$ bucks goes forward with it…. :wink: :+1:

Oh, don’t get me wrong… I’m not saying I wouldn’t like to try it out and see, but at the price point, the offset COB design, and the extremely high amp requirements, I don’t see myself doing anything with this one for quite a while.

When you want max throw, you can throw efficiency out the window.
The point is to get the highest possible numbers, and this is currently #3 on the list of highest intensity LEDs.
What’s so cool about it is that it can do this while also outputting a huge amount of lumens, which the first two don’t do.

Perfect LED for applications such as moving heads, which are starting to transition to LED:

And sky beams which are currently all short-arc:

.
Neither of these are “flashlights” and neither of them are “budget” so the majority of people on this forum won’t really get excited by this LED :stuck_out_tongue:

So hypothetically, what kind of numbers would be seen in a BLF GT sized reflector?

2.3Mcd, ~3km throw
~4k lumens in spot, ~1.2k in spill.
265m spot diameter at 1km
10 degree beam divergence.

I indeed did not take the domelessness (is this a word? :innocent: ) of the CFT-90 into account in my calculation, that makes a big difference.

If any host is suitable for this led it must be the BLF-GT, in fact its bulkiness and that it takes 8x 18650 batteries makes it more tailormade for the CFT-90 than for the XHP35, as if the GT temporarily is fitted with a XHP35 but in reality was waiting for this led :slight_smile: .

High thermal mass doesn’t necessarily mean high thermal dissipation, if this LED was driven anywhere near its max in a GT it would overheat instantly.
I wouldn’t recommend it for any ‘normal’ flashlight form factor, more for something with AT LEAST a fan cooled heatsink, or preferably liquid cooling.

Mind that a well-fixed Q8 runs at over 20A already, at a comparable voltage, so half the current of the CFT-90 at maximum output, and does that for 3 minutes without getting worryingly hot. With its larger mass and surface area the GT should be able to run the CFT-90 at over 40 A for three minutes too before stepping down.

First of all, the heat from a Q8 is spread out over 4 points, the CFT90 is a single LED so the junction temperature will be 8x higher than a Q8 (since it will be producing 2x the heat output).
For this reason you would need to use a large copper base heatsink, or a TEC.

Second, the surface area of the GT is probably close to 10% that of the heatsink used in SMA’s test. Heatsinks have tens or hundreds of times more surface area than a flashlight like the GT with its few shallow fins.

Third, the mass doesn’t matter at all for heat dissipation, it’s just an energy reservoir.
If all you care about is a few seconds of high output then sure, the GT will work, but for practical purpouses and actually using the light for more than a few minutes on max it needs to have much higher thermal dissipation.

Personally I think any light that can’t maintain its max output for long periods of time is basically useless, it may as well not have that max setting.
Which is why I hate lights that are direct drive.

^ It is an ongoing discussion on BLF how desirable high output/fast stepdown flashlights are. For maintaining the high output of the CFT-90 for longer time the GT will not suffice, but I’m sure someone will do the mod :smiley: and I’m curious what runtime on max it will have :slight_smile:

Ah come on if those 25K+ lumen lights offer enough fun for a few second to such extend people buy it, sure seeing this monster led in the GT should be awesome :smiley:

+1 hope the price comes down and efficiency go up…

Might as well just make a flashlight with a flash bulb so you get those 100k lumens for 1/10th of a second…
People buy dumb things just because of marketing, such as 25k lumens for 30 seconds.

this is not true, the CFT90 has 0.45K/W to the heat sink, while a XPL has 2.2K/W to solder pad
the MCPCB mount adds a bit to that so probably 2.5K/W

so at 20A the CFT90 die stays cooler

+1

If a light can not sustain MAX output for at least a few minutes it is USELESS to me. I categorize it as a WOW light which is impractical for normal use at that level.

A lot of people buy these modded lights from V54 and others just for that[The WOW factor]. These people do not even use the lights that much! Within weeks or a few months a lot of them are up for sale!

To each his own.

Those lights are useless to CAPO and I on the trail. The longer a light can sustain MAX,the better. That is my preference.

I know several people who probably have a 10K plus collection primarily for that WOW factor and not for every day use. They are entitled to their preference also although I do not understand it.

Turbo mode on my D4 steps down after 10 seconds.
Unless I turn it off before that, which happens half of the time. And I do because I use it to take a glimpse of a place that’s dark with the mode that I use at the time.
So yes, this turbo is actually useful for some people.

Despite not being able to cool this monster led on max, the GT still seems the best flashlight to try it in, just image what beam at not max amps will give :smiley:

Basically the same as the XHP35 HI since the die size is very similar, just a bit brighter from a few more lumens.

We are all different. I returned my D1vn after using it once on the trail. It got so hot, so quickly[to be expected but still disappointing].

I was able to set the driver and get it to run for 1:30 on turbo. By that point it was so hot you could not even run the light on 50%. I had to let it cool for a few minutes. These small lights are so powerful that there is no way for the heat sinking to dissipate all that heat.

For me a 10 sec. or 20 second burst is useless. That is just me and probably some others. I will admit I love Max output. My K40vn,TK61vn,M2Xvn and some others ALL can run at least 20 minutes on max b/4 they get too hot. The M2Xvn NEVER gets hot and can stay on max continuously until I put a fresh battery in. Then again, this light is only 1200 lumens and a much bigger light compared to the D1vn!

So the lesson I have learned is that these SMALL/POWERFUL[Even bigger lights that get too hot too quickly] lights have know practical use for me on the trail.

My smallest light for the trail is my TX25C2vn DD/Single mode XPG2. The rest are mid ranged and large torches.