MF01 Vs MF01S Efficiency / Sustained output

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Th558's picture
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MF01 Vs MF01S Efficiency / Sustained output

So for a while I’ve noticed that the MF01S 4000K gets considerably hotter than the MF01 Nichia at the same output. I’ve just seen a review which confirms my suspicions about the MF01S being far less efficient. In the video he does a runtime test and the MF01S struggles to maintain the same output as the MF01. It keeps ramping up and down whereas the MF01 decreases in output very slowly over the course of the test. Not only that, but the MF01 only gets to 46°C whereas the MF01S hits 65°C. Correct me if I’m wrong but the efficiency difference between the LEDs is a bit over 30% at low levels so why is one getting significantly hotter with less output and shorter runtimes? I know the efficiency difference isn’t small but it still doesn’t seem to reflect what the graphs are showing. The MF01S might have double the candela but what is the point of having that advantage when it can only sustain half the output? Even my FW21 Pro can sustain about the same output. I know the MF01S uses a FET driver. Not sure about the MF01, I think there were two variations of the driver in that light. I also had suspected that maybe the smaller footprint of emitters makes the thermal transfer worse but according to the graph in this video, it seems to be more of an efficiency issue.

Can someone explain what is going on here? Is it the inefficient LEDs + inefficient driver which is causing the huge difference in power consumption?

Graph is at 9:50

Edited by: Th558 on 09/07/2021 - 22:07
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Well, the light needs to dissipate heat, by around 5 minutes MF01s would have accumulated a lot of heat due to the extended turbo runtime, short of switching it off, if there is no outlet for that heat to dissipate it’s going to struggle.
The Nichia version appears to step down after a much shorter time and doesn’t accumulate as much heat. Try turning on the MF01s in a lower mode and see how much it can sustain without a turbo run, if the Nichia version can sustain 2200 lumens at below 46 degrees, then I’d suggest the sst version should be able to sustain a higher output driven at the same level.

thefreeman's picture
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The MF01 (v2) uses a boost driver (2S to 18V), I measured the efficiency at some point but can’t find my notes, IIRC it was arround 90~93% approximately at the sustained output.

The MF01S is a direct drive FET plus some amount of 7135s so it’s less efficient, on top of that there seems to be a problem with the thermal regulation.

Quadrupel's picture
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This graph is nice example off boost driver advantage vs linear

Sidney Stratton
Sidney Stratton's picture
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Again I see improper thermal management with Anduril (in reference to the FT03S) – ported without tweaking TK’s PID. Seems a recurring theme with Astrolux.

zoulas's picture
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I have both lights in SST20 and I don’t see the immediate drop in lumens that the graph depicts. Actually, they both seem to sustain high output for a respectable amount of time.