I understand you also. But if i am honest with myself, that “feature” is very silly. I cannot think of a single person that will actually use it, and even less to make a difference for them to buy the light or not. As i said peoples preference and choice will be much more influenced from R9 values and rosy tint at 3000 or 4000k. Changing tint between 3000 and 4000k is not really a real feature, it is a gimmick - if we are honest.
Please, do not be offended, I am talking with the uttermost respect, but am trying to be realistic.
Well, I have a use for tint ramping. I like 5000K for work lights because that colour temperature seems more natural to me when I’m doing repairs or moving stuff around the attic, but 3000K is better for reading and relaxing in the evening before bed.
The plan is for the lantern to support a ramp between 3000K and 5000K (not 4000K), so the feature is ideal for me. I can save money by only buying one device for both scenarios, or I can buy two to have a backup with both units being able to do everything.
Much better than having one 3000K light and one 5000K light, where Murphy’s law guarantees that the one that breaks is the one you’d rather have right now
Being a flashaholic, I like gimmicks as much as I like useful features for real life. “Hey, that sounds cool, can we make that?” is part of the fun of BLF projects and the price that real people pay is extra features that may not neccessarily aid to their real life. Luckily some people even have a need for the gimmicks
Without that feature, I don’t know that I would still be interested in this light. This feature would also help sell to many who don’t care about this feature, but have a preferred temp. With the ability to satisfy people with a temperature preference between 3000K-5000k you cover a lot of people.
My temp preference is 4000K 99% of the time. For most scenarios I can use this at 4000K. For camping and a few other times 2700-3000K is needed. On the rare occasions that I would use it during the day I prefer 4500-5000K for that.
Yeah, if you go back and read all the discussion from the start, you will see that the tint ramping was added just to make sure this light does cover pretty much everyone. Unless you have a strong preference for a tint which is either higher or lower than the range provided, then protesting this feature is quite a selfish and arrogant thing to do, IMHO. We aren’t a mono-culture here.
Not only that, but the tint ramping feature isn’t even a big deal from a design (or build) perspective. It doesn’t much affect the complexity of the hardware or the software, compared to recent BLF designs. The big deal, design-wise, is our attempt to add on-board charging to the driver. From Sofirn’s perspective, that still won’t be a big deal either, once we get a PCB layout (and a BOM) for them to follow.
The main complexity of tint-ramping is indeed not in the hardware (driver design is a bit different but DEL first and Lexel now is working on that, and the MCPCB has a different lay-out which is nothing complex), but the main complexity is in the software and the work on that will be done by our in-house software-empress Toykeeper. The Sofirn part will be finding the right 3000K and 5000K leds, and letting Toykeeper have a prototype to fine-tune the settings.
Good points djozz. As of right now were hoping to go with efficient Samsung LH351D in both 3000Kor 2700K) and either 4000K or 5000K for the cooler side if we can get the tint ramping feature integrated.
There is no doubt in my mind that Toykeeper is fully capable of this. The hardware is easy (and done), the firmware is not much different than what already exists in Anduril.
The very warm to neutral customizable high CRI tint and promise of the complex software features are what drew me to this light. If I wanted something relatively simple I’d just buy Zanflare T1 lanterns and never bother with a more premium lantern at all. I am buying a Zanflare T1 anyway, but that’s just because I’m a flashaholic and can’t stop myself…
Quite a few people (myself included) would use that feature and it is a big selling point. Without that “silly” feature and a great UI (what ToyKeeper has mentioned of the UI sounded quite enticing), I don’t think there would be enough to compel me to buy it over other cheaper lanterns or a diffuser.
The bigger the spread the better, in my opinion. The Samsung LH351Ds from what I’ve seen are an excellent choice.
Someone has to design it. Designing parts of this lantern has been slow sofar, only now even the driver takes final form and I believe it is nice that it is being done at all and that it will have nice options and firmware. And an even more efficient driver without PWM like you suggest (I agree that for a relatively low-powered light like the lantern a FET-based lineair driver would be a suitable application) would require lots of extra expertise and time. Apart from that, I wonder if you could get output and tint ramping done without old-school PWM?
I will suggest to the manufacturer to try to source the 351Ds in 2700K for the warm side and 5000K for the cool side of the two channels for tint ramping, that will give a good range of tints.
I think it is too much to ask for Sofirn, but if you never ask for it you will certainly not get it:
Could you ask for the 2700K led for one of the colour-bins W1 to W8, and for the 5000K leds for colour-bins R1 or R2? These Samsung tint bins are on or below the black body line, if Sofirn was able to source them (in 90 CRI of course) that would be awesome for the tint of the Lantern.
I am in search of a bit of education in regards to efficiency and driving LEDs. In the area where I am familiar, power supply design, PWM kicks the doors off efficiency vs linear every day of the week. What is it about the LEDs that this is not so? Is it that the voltage drop across the linear regulator is small, due to the close LED Vf and the prime voltage source (rechargable lithium battery)? Or PWM plus the linear current regulators is double loss? I would be interested to read more about this if someone can point to some reference material.
It’s the LED itself. Lower current = more lumens/W. Some of it is due to less heat (which I think does not change significantly with or without PWM) but I believe some of it is intrinsic to the conversion of electricity to light. And that part means more efficiency by running at say 1 mA than at 100 mA with 1% duty cycle.
And the PWM we talk about here is not the PWM of power supplies. It’s a duty cycle for a linear regulator… nothing efficient about it. Some drivers do have more efficient design of course, much like modern power supplies.
One last thing: I don’t know about the LEDs being discussed here but some change tint and probably CRI too depending on current. So a linear driver might not be desirable at all because of that.
And I learned most of that around here. Couldn’t dig up the exact threads but djozz’s LED test threads are usually a good place to start to read technical discussions. So are the driver design threads. Unfortunately some of it may be lost in other places. Stick around and the information will eventually percolate lol
@DBSAR, I have already spoken to Sofirn about the bin tints and LED tints to use with the right order code. That was a WHILE back though, so they may not remember about it.
However, if Barry can confirm which LEDs they’re using, they should be these, if I’m not wrong:
@sbslider, this is in regards to the type of linear regulator used. It can either be a single purpose linear regulator, like a 7135, or a FET used as a linear regulator
FET as a linear regulator, will always be better, but let me explain.
- A single purpose linear regulator will run at a constant current set by its specs at 350mA.
If ran at 100% duty cycle, the linear regulator will output 350mA to the LED.
If ran at 50% duty cycle, the linear regulator will output AN AVERAGE OF 175mA, meaning the LED will still see 350mA, but at half the time. This is what we usually do in linear drivers. However, they don’t behave well at thousands of hz, and the efficiency of the LED stays constant, even though the average current will be lower. While in fact, it should be more efficient.
This is where the FET as a linear regulator is very useful, rated at say 350mA.
- If ran at 50% duty cycle, it will output a constant 175mA, meaning the LED will now see 175mA, and its efficiency will be increased at lower current, along with the FET easily handling 100s of kHz of frequency, removing parasitic inefficiencies.
