That spot is also an artifact of the domes AFAIK, but can also be caused by uneven application of the phosphor on the LEDs, you can see the color differences when lit up in very low current with a different color center.
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That’s exactly what is happening, uneven phosphor application, specially on the middle between the dies. I can see some blue looking straight down into the reflector.
That’s how it looks on a white wall.
Saturation boosted to 400% to highlight the blue spot.
Not really a problem for me, and I’m not disassembling it again until Cree decides to release the 95CRI XHP50.3 HI 5700K in 3V.
The phosphor coverage over the entire substrate is something that appeared with the advent of flip chip technology. It’s responsible for the greenish aura around the hot spot, which is not tint shift. The blue tint in the center of the hot spot is a result if quad die technology, yes the gap between emitters ( improved in the quad dies that have less space between them). Again, this isn’t tint shift.
When an emitter has a greenish hue at low output and a blue/white hue at high output, like the SST40 often shows, this is ( to me ) the epitome of tint shift.
A lot of people like a warmer tint, some like the extra power of the blue/white 6500K+ emitters, but few like the sickly green hues.
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How’s the hip? Did you go with the robotic assist?
Yes, went well, alignment is perfect… zero strange feelings. Walking good, was up to 5 miles a day until I pulled the lifting stunt. Walked 1.3 miles this morning so I’m bouncing back pretty quick from my dumb moment.
First week or so was pretty intense. Just over 4 weeks now and the muscular healing is coming along nicely, as long as I do my part and move smart. Easy to damage the muscles in my thigh for now. Guess a 140 lb scooter is substantially more than the Dr would allow. 
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What do you call this then? I’d prefer to call this phenomena something different than current- related tint changes, but as far as I can tell most of us use “tint shift” interchangeably.
I call it messed up and get out my Scalpel! Dice that excess phosphor off, problem solved!
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For the blue spot cause by the quad die LED i say “blue leak”, but for the tint uniformity problem i don’ know, i used to call it tint shift too.
The way I see it is there’s two kinds of tint shift: one is caused by the increase of drive current (what happens with the SST40) and the other is caused by the angle of incidence of the light coming from the source (tint measured directly above the LED vs measured at an angle) and i usually know which one is it by the context, but it’s not always possible to differentiate them correctly.
Idk either. Sometimes I’ll say “tint shift from the hotspot outwards”. Or “tint shift between the hotspot and corona and/or spill” or “throughout the beam” or w/e. Should have an actual term for it probably.
Hi.
I wonder what firmware I should use for a “Sofirn Q8 Plus”? (which has a t1616)
Is this the right one?
I have flashed my original “BLF Q8” many times with my custom version of Anduril 2 that I compiled in Microchip Studio.
All I need to know is which source to use as I couldn’t find a specific “Sofirn Q8 Plus” version.
Many thanks in advance.
I don’t know, because manufacturers do all sorts of unpredictable things with the firmware… but there’s a reliable way to find out:
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Do you mind if I ask where you bought the FETs from for the Sofirn Q8 Plus?
I managed to blow something up (FET or 7135?) by using three high drain Lishen cells. I didn’t make any modifications. The Q8 Plus from an earlier batch came with 6500K emitters, 20awg wire for the driver, and it came with the springs bypassed.
I measured about 28.9k lumens at turn on but two emitters are constantly stuck on now:
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I have bought mosfets for EC06 from Aliexpress. I just searched that part number written on top of them.
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I buy MOSFET’s from an electronics supply named Mouser. A ton of research goes into exactly which one. Sorry this is so late. And so vague. I don’t built lights anymore and my strongest attribute these days seems to be forgetfulness.
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Q8+ stock mosfets run outside of their specs if you check datasheet. Not very good ones for under 4V if I remember correctly. Resistance rises greatly lower the voltages go. Still I chose them, because I was too lazy to search better ones. I did a mod using SFN55.2’s and they had even lower VF than 50.2’s. That caused the mosfets to heat like crazy and if turboing longer than 5 seconds, wires desoldered themselves from pads next to them. I must have resoldered them like ten times. Something related might have happened with OP’s light also.
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