Short but thorough comparison.
For some reason Simon refused sending me both SFT90 and LHP73B, so I had to request he include the SFT90 mcpcb to swap in. Had to record everything twice, while trying to get everything synced for the video, bit of a nightmare to edit. His response was that both LEDs were very similar, however, they’re quite different.
Is Vpcell H50 a good choice for this light?
The H50 seems to be a rewrapped Tenpower 50XG, so yes, it’s an excellent cell.
Thanks, I was waiting for your review of the M21K. SFT-90 is a bit more throwy but its high Vf and nasty cool white tint can be a no-go for many people. If someone wants more throw I’d wait for the new round high power emitter from Convoy.
What are the expectations?
SBT90.2 alternative shrunk down to 7x7mm, 30A max current and available in different CCTs (3000K-6000K).
If the performance is there once it comes out both SBT90 and SFT90 will instantly become obsolete.
I really hope it performs well at 20A, I’d hate it to require the 30A to be comparable.
Sweet!
I love hearing about new emitters that might be better than the competition. 
It doesn’t have a massive LES or footprint, there’s no reason why it would be particularly efficient at the highest current. Also Simon said it can withstand 30A, maybe max current will be lower? I only hope it beats Luminus when it comes to brightness.
Just by some pixel measuring, the round die emitter will have closer to 12mm^2 of LES rather than the SFT90’s 9.6mm^2. So given the same current, it will almost surely perform better in output (due to lower power density), and for the same reason, worse in throw.
I’ll gladly trade a bit of range for a wider hotspot in 5000K though.
It looks to be a derivative of/from FFL909MX, technically larger LES (altough visually doesn’t look like it) but also better throw on highest mode:
https://www.reddit.com/r/flashlight/comments/1hyrprv/dethroning_the_sbt902/
Also even if it’s just going to match Luminus that’s great as it’s going to be a perfect blend of nice tint and good throw because as for now you have to choose either or. It will be a great option for smaller models like M21B or M21H where LHP73B is mostly flood (25 mm² of LES) and SFT-90 has a really nice balanced beam profile but it’s just nasty cool white (+high Vf so it runs hot). If the new emitter delivers it’s going to be the best of both worlds especially if they’re going to manage to squeeze more lumens as well (big if, hopefully).
I’m hesitant to use the FFL909MX as a basis for comparison, as (1) its LES has not been measured, (2) it is substantially greener than SBT90.2, whereas Simon’s emitter will be pinker and thus lose some lumen count, and (3) the smaller 7070 footprint may handicap performance.
In any case it should be a generally more usable emitter, just for the CCT/tint alone.
They are definitely related and you can tell a lot for example about beam profile. Also going less green didn’t really compromised the output of the LHP73B compared to SFH55 (altough we don’t know the output of the base round model).
Again, I am hesitant to speculate. For example, the SFT25R 5050 looks exactly like the SFT25R 3535, and it is natural to assume that they are related, but dissection reveals that they use different dies.
At 30A (where the LHP73B test ends), the LHP73B achieves under 8900lm, while the SFH55 hits 10,000. It’s unclear how much of this is attributable to the larger footprint, and how much to CCT (likely very little since the spectral efficacy levels out and falls as a function of CCT) and tint.
But beam profile is basically identical.
Yes, larger footprint is the most likely a reason why SFH scales better at high currents but it’s also a good sign for the new LED - if it can handle 30A maybe there won’t be much of a performance hit at 20A. Hopefully, it’s all pure speculation.
There is little one can infer about the beam profile without side-by-side shots on a wall from a good distance (say 10m) away, which allows the beam to converge to its final shape. If anything, the short distance beamshots seem to hint at the SBT90.2 being more intense than the FFL, but again, short distance beamshots provide really very little information about throwers:
I do not find official ratings for LEDs particularly meaningful–for example, the SFT40 3000K and Nichia 519A are generally driven at more than double the rated current with no issue, while the SFT40 5000K turns bluish well within the rated current. But given that the SFT90 maxes out around 20A, the 30A rating of the new emitter does sound promising.
Yes, only time will tell. I wouldn’t count on seeing this emitter until at least a year out, and wouldn’t invest too much excitement as there’s no telling which projects come to fruition, and which ones disappear before completion.
Longer distance:
https://www.reddit.com/r/flashlight/comments/1hyy7b1/ffl909mx_bean_shot/
Close enough. Pretty much the same beam profile and slightly higher brightness/intensity. It looks promising, that’s it. That’s also why I’m holding off from buying M21H with LHP73B because maybe in a few weeks/months we’ll get a perfect (less floody) emitter for smaller hotrods.
Thanks for the shots! It looks like the FFL is out-throwing the SBT90.2 by having much more output; it is unclear whether it is much more efficient or driven harder. In any case Convoy’s version will be a more generally useful emitter than the LHP73B.
I don’t know why would FFL use different drivers for 3V emitters in the same flashlight so I’m hopeful it actually is just brighter.
