Hi everyone

We have sent out the ROT66 Osram for testing. Will be back soon to take care of the issue.

It wasn’t even tested for lumens before announcing the numbers?

So what am I supposed to do right now? All the accessories I bought at full price already shipped , the flashlight is in processing on banggood. Should I try to cancel the order? How can this be fixed once I receive it??

You buy the Osram version for the throw, not lumens. The 2mm white flat will throw the furthest out of any of the LEDs offered.

i think they saw that the white 2 does 1500 at max so they just multiplied that by 12. I asked them when lumen measurements are taken and they said at turn on….looks like they aren’t even taken. just estimated.

Just theoretically estimated like that? Oh my goodness…

That’s theoretical. 1500 lumens theoretical max output, but that’s ideal conditions with heat not being an issue, and driven at a very specific amperage.

In a flashlight host, and driven with a fet driver, you’re not going to get close to that. The highest I’ve seen the 2mm whtie do is 1200 lumens in a Vinh modified D4s. On average it does more like 800-1000lumens per led.

Form sent

I just canceled my order for the Osram rot66 with banggood. This was most upsetting relying on the advertized numbers which were not even tested. Unfortunately the accessories I had ordered for the light already got shipped. If someone wants them, the AR glass, steel tail cap, diffuser, I will sell with a discount when I receive. Thanks

Has anyone tested/ verified the lumens for the other versions like XPLhi for example? I was really looking forward to this light. Maybe I can order a different version if that was verified?? Anyone who already has a version of this light can shed some light? ( pun intended). This way I could still reuse the accessories ….

I think Fireflies got that number by calculating 12 x 1.5k lumens = 18k lumens since a single emitter W2 can achieve 1.5k lumens. Most flashlight manufacturers do not have any lumen testing equipment unless they are the big manufacturers like Olight, Acebeam, Fenix, Nitecore, Thrunite, so 90% of the ratings are from guessing. Also even the ones with lumen testing equipment might have it calibrated differently. For example, Acebeam ratings are higher than our Maukka calibration despite their throw ratings are conservative. Olight and Fenix measures closest to Maukka lights. Also to point out, I have 4 different Maukka calibration lights. If I calibrate my lumen tube to one calibration light, it could be up to 10% off when measuring another calibration light with different beam pattern and CCT, so most of our measurements with non professional equipment are not super precise. I will also test my ROT66 when I receive it.

Cloud,I would recommend you look at a D18 or MF01S. I have both of these lights and they are excellent and they actually do what they say they’re going to do as far as output and throw. I understand all the experts chiming in with the technical interpretation of how some of the light manufacturers get their figures however in this case on a $100 plus flashlight to have half the amount of estimated lumens and throw is inexcusable and cannot be defended in my opinion. I have the original version of the rot66 in xpl hi and supposedly it pumps out 10000 lumens it probably puts out closer to 7 or 8. I can deal with that much discrepancy in output but not 50% especially at this price. That being said if people test the OSRAM version and it truly does way closer to the Lumen and throw estimates I’ll be more than happy to buy one. I have every one of the fireflies products and I’m very pleased with all of them I just need to be paying for what is advertised. I hope this helps you and others in the same predicament and I also again want to thank the extremely helpful expertise that is shared on this forum it helps people like me out tremendously and I thank you all that continue to do so.

Thank you
Yes I was actually trying to pick between rot66, mf01 , or D18.
Jack from ff-tot responded to me and I was starting to think maybe buy a different rot66, like XPL hi, he says the lumens are more than 10k close to what’s advertized now. Not sure which is more correct , you think it’s more like 7 or 8? I like the geometry and shape and lightness of rot66 so am kinda inclined to do that but I definitelrty need something stronger than 7 or 8. It’s interesting that the d18 and mf01 is exactly what I was looking to choose from. Still thinking….thank you!!

SKY69, I hate to say it, but the two flashlights you mentioned, D18 and MF01S, also don’t (usually) reach their full advertised output, even in ideal scenarios. While I do agree that Fireflies should have advertised a more realistic number of lumens, the reactions in this thread are excessive and unwarranted.

MF01S with SST-20 4000K CRI95 was measured at 8500 lumens with Samsung 30Q cells. Note that MF01S is advertised at 15k lumens, but there are multiple emitters options. It is understood that 15k lumens is an estimate for SST-20 6500K CRI70 emitters, which are known to have higher output than SST-20 4000K CRI95, but only one number is advertised by the manufacturer.

Someone else measured an MF01S with SST-20 4000K CRI95 at 10080 lumens.

D18 with SST-20 4000K CRI95 emitters was measured at 7500 lumens.

Here are some measurements of D18 with SST-20 6500K CRI70. Someone did measure 14k lumens, but only with Sony VTC5A.

Keep in mind that Fireflies does not always overestimate the number of lumens. Fireflies E07 with XP-L HI V3 emitters is advertised at 6900 lumens, but has been measured to be 7500 lumens with Samsung 30T.

Measuring lumens accurately is hard. Any numbers you see could be off by 10% or more, especially if the measurements are not done using the same equipment by the same person.

There are other considerations.

Flashlights with FET drivers, for any given pair of batteries, will have the absolute maximum reading for lumens only briefly while they are fully charged, and it will go down quickly. To achieve absolute maximum output, you need to use a high-drain low-capacity set of batteries like Molicel P26A or Samsung 25S. This advantage only lasts very briefly as they get discharged rapidly, and in practice Samsung 30Qs provide more output for longer and are more useful for all purposes except measuring maximum output at turn on. Fireflies E07 was measured at 6640 lumens with Molicel P26A and 5650 lumens with Sony VTC6. That’s 15% less, even though both are good high-drain batteries.

Heat is also an issue. Compact lightweight flashlights like ROT66 Gen II cannot sustain output at full turbo for very long. If you could supply enough power to get 18k lumens from 12 emitters, the body would become too hot to hold in a few seconds. Efficiency goes down rapidly as you increase power; it is not simply a 2x increase in heat to go from 9k lumens to 18k lumens. It could be 3x or even 5x more heat, or worse.

Are you aware that it takes 4x as many lumens for a flashlight to appear 2x as bright? If you don’t measure the output, you might not be able to tell the difference between 10k lumens and 13k lumens. A 30% difference in output is too small to be noticeable. However, if it takes 2x more heat and power to get 30% more output, you will definitely notice the increase in heat, and your batteries will die much faster.

XPL HI outputs more than 2mm white. It’s a much larger LED.

Lightdecay, I don’t think the reactions here are excessive or inadequate. When one finds out something like this he would naturally feel taken for a ride. I mean this just shouldn’t be happening. While everything You said is very valid and appreciated, the problem is not that there could be different measurements by different people, or that one can use different batteries and get somewhat different results, or other differing conditions, and not that some lights might exceed the claimed luminance and others don’t.

The problem is that the main parameters are advertized based on not very reliable theoretical notions in order to command higher revenue and without even prior testing. I understand some manufacturers may not have accurate testing equipment. But if I was a manufacturer making fireflies and without testing equipment, the least I would do before promising my customers attractive numbers, I’d hold my one tested 14, 000 version rot66 in left hand and the other ( Osram) version in right hand, point to the ceiling and turn them on one after another, and that’d be no way I would believe that the 9,000 lumen rot66 in my right hand is brighter.
And you know what? If other lights/ manufacturers overstate their lumens that does not make it ok for everyone to do so. On the contrary, it should be talked about the same way so people who spend high$$ for these novelty features are also protected.

So I think we have been civil in discussing it and there has been a mistake made by fireflies, hope they find a way to more accurately estimate the output or a type of standard that laymen can relate to can be established in the future so people know what they are paying for.

Lightdecay, I don’t think it’s excessive to be disappointed by a $100 plus flashlight that has grossly over estimated their outputs. I said nothing excessive in expressing my opinion on this and I have all the other Fireflies lights and am happy with them. I also said that if they test the ROT66 OSRAM version and its closer to advertised throw and output I will be glad to buy one. Also you should look at two reviews by Flashaholics on youtube. The MF01S is tested at it’s advertised rating and so did the high CRI version of the D18S. Have both lights and they are impressive both are less expensive also. I value all opinions on the forum.

I forgot to metion that I agree with Twisted Raven that you buy the OSRAM for throw not lumens and that is why I still want the light. My concern is if the output estimate is that far off then the throw numbers might be too. That is why I cancelled the order. It’s too much hassle to return a light better to wait and buy it right. I hope the throw numbers are close to what Fireflies expects because I still have hopes of buying one.

Throw numbers will be lower too.

I have canceled the preorder. 21 days waiting and false power estimates have been too much for me.

I ordered a ROT66 Gen II from BG on 9/26/2019 and it’s still “processing”… I refuse to do any business with any Chinese company where I cannot use PayPal for processing. If nothing else I can go to PP and dispute an order. 3X now I’ve live chatted with BG to find out why my order is stuck in limbo and get the same pat answer…. “Someone will email you within 24-48 hrs. Which they never do. I know one thing. I will never ever order from them again. I am very disappointed in the whole mess.

So now I’m guessing that the GEN II I ordered is also less than advertised output? The XPL HI V3 6500K 14000 lumens ?? I stopped purchasing flashlights for some time because of lower than advertised lumen output. So anyone know the deal on the XPL HI V3 6500K 14000 lumen emitters? Are they over-estimated as well? Just frustrating. And I don’t consider my frustration excessive either. $100 is a lot to some of us.