Whoops, I missed that.
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To clearify that, I had to change the driver, now it works.
The other modes worked like they should, just the Mode 10 that I use for all my lights didn’t.
Bought one of the 5000K R9080 NV1010s… That will be transfered onto the 20mm MCPCB that is in my NV1010-Modded S15
Thanks, didn’t think of that. It’s a black M21A that’s been emitter and driver swapped many times. I had the red switch already installed on the previous swap, the FL707MD, and just left it to match when I swapped in the CULPM1.23.
This 2.5V driver seems to be the only convoy driver I’ve ever seen where the 0.1% mode is actually at moonlight levels, probably the vF and all that. Thought it wasn’t even on at first. Too bad most/all the other driver’s 0.1% mode are way too bright.
Could that 0.1% mode be something that could possibly be changed? Or is it “baked” into the hard/firmware?
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That’s very interesting–I also noticed this and measured the 0.1% mode as 40x dimmer than the 1% mode, which makes it a true moonlight. However, they consume about the same amount of power (something like 13 vs 17mA), so the 0.1% mode comes with a massive hit in efficiency.
It seems that the driver alone eats up around 13mA, independently of the LED–I’m guessing this because this part of the current does not get reduced when I resistor-swap Convoy buck drivers for lower current. I think this also suggests that Vf is not the reason for the low moonlight–it’s a quirk of the firmware.
My guess would be that it’s baked into the firmware–one can only change the absolute brightness of levels via resistor swaps, but not relative percentages. Maybe there is a way to do it for those who are more savvy in driver design, but not the casual hobbyist.
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Thanks much!
I think there are only a few drivers that would allow for an adequately low moonlight in an S2+ or similar lights. I have one with H17FX which is nice. Maybe the dragon driver? My bistro MTN17-Ddm has a decent moon but I’d like it to be a bit lower. It lives in a Reylight Gemini.
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Yeah one annoying thing about Convoy drivers is that they don’t have a proper moonlight–the 0.1% mode is usually much brighter than 0.1% of the maximum output. I’ve been getting around this issue by using the illuminated tailcap as a moonlight. I used to have Mtn drivers–their FET-only drivers had pretty decent moonlight when the battery was low.
Here’s a post where I swapped the tailcap LEDs with (1) a SunLike 2835 for moonlight, and (2) a red-green combo for voltage indication. It’s pretty easy to pull off, especially the former as the 2835 is a pretty large component to work with.
For just moonlight, you can scrap the values suggested in the text of that post, and just replace the stock LEDs with 2835 LEDs on thin copper wire. The stock 300 Ohm resistors will make it pretty bright, but still substantially dimmer than the main emitter on 0.1%, for a white light driver.
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Looking at the new SFT-60 options with the 15A driver.
It looks like the Vf of the SFT-60 is going to be around 3.5-3.7V at that current (probably towards the higher side). Even a high-drain tabless 21700 is going to sag very quickly to around 3.9V under load, and then adding driver losses, it seems like it may drop out of regulation very quickly even after fully charging the cell.
Does anyone have any experience with this emitter? Does this mean that even if used only in short bursts (allowing it to cool down in between), it will only perform well with a fully charged battery, and the throw will be significantly worse as the cell discharges?
Especially compared to the SFT-42R, which has quite a bit more headroom due to the lower Vf and battery sag at 10A. Though, on the other hand, it seems like the 15A driver doesn’t step down as fast as the 10A?
No experience with this emitter, but physics does say that the SFT60 is much worse at sustaining throw than SFT42R, due to increased heat generation and battery consumption, and the larger LES. The reasoning you gave about Vf rise and voltage sag also does seem to hold up.
That is unclear–it would seem to me that the 15A has to step down faster due to increased heat generation. The default 10A driver for L21B is known for premature stepdown, but it is reported that the 17mm 10A driver has no such issue. It can be used with an adaptor.
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I have a couple SFT-60 and 15A buck drivers in now and was planning on converting my L21B with SFT-40 and 10A driver into the aformentioned setup.
Unfortunately not much time the coming days to actually do this.
I’m also curious how the SFT-60 will perform in a multi emitter, multi battery light like the Q8 Plus.
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With that high Vf, SFT60 may be very good choice for flashlights with 2 serial cells, and buck driver like M21G or M21J and L6 or L7.
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What about using an EVE 50PL? Will the voltage sag too?
Looks like it’s going to depend a lot on the individual Vf of the emitter you happen to get, since for the VJ forward voltage bin, you could get anything from 2.7V (at 1.5A) to 2.9V (at 1.5A). Eyeballing the discharge curve of the 50PL, that means you might be able to stay regulated for half the capacity of the 50PL if you win the Vf lottery, but on the other hand, if you get one at the high end, it’s going to drop out of regulation almost right away.
With the SFT42R at least you have a little more headroom.
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actually sft42r at 10A vf about 3.46v, sft60 is about 3.28v that’s vj bin convoy sells, if you want to compare to 15A sft60 that’s about 3.48v, i think 60 is better in terms of vf
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That part is true - at the same current, the SFT60 has a lower Vf (as expected from the larger die). However, with the 15A driver specifically, you not only have a similar Vf as the SFT42R (at 10A), but also get more voltage sag from the battery and more spring/wire/driver losses. Those are what will drop you out of regulation faster with a buck driver.
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running 60 at 15A is bad idea, only just for kicks, since it’s about max current and you get big drop in efficiency, 10A is the best current to use
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I think you’re right. It’s just a pity because at 15A it comes so close to being a ‘holy grail’ that can throw almost as far as an SFT25R, while having nearly as many overall lumens as an SFT90, in a single cell light. If only it could sustain that a little longer…perhaps we’ll get there in another 5 years.
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How do you know what the Vf is on the SFT60 at 15 amps? Did I miss something?
The datasheet was posted online:
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