0. People who don’t care about tint and CRI are wrong.
The SST-20 has more cd/lm such that a low-CRI SST-20 will have more intensity than any XP-L HI in most reasonable optics, and a high-CRI SST-20 will at least equal a high flux bin XP-L HI.
Whether the SST-20 uses more current depends on the driver. Having lower forward voltage, it pulls more current with a FET driver (e.g. in my Astrolux SS with a VTC6, the XP-L HI was 4.0A and the SST-20 is 5.2A). With a regulated driver, there’s no change in current and output will be stable longer.
Luminous efficacy (efficiency) is lower for the SST-20. That means a little more heat at the same current. With a FET driver where the SST-20 pulls more current, it’s substantially more heat.
With a regulated driver, a high flux bin XP-L HI will have a little more output than any SST-20. With a FET driver, that’s uncertain and may depend on details like the number of emitters, total resistance of the circuit, and battery used. The high-CRI SST-20 in my SS is a little behind the original XP-L HI in output, but I suspect the low-CRI version would exceed it.
No one is suggesting buying a 70 CRI SST-20. Maybe for tint over an XP-L HD, but almost no one is buying 6500k who cares about tint.
The Cree has the raw lumen numbers and good marketing. The XP-L HI is a much nicer emitter to look at then the XP-L HD and certainly an SST-20 at low currents (green).
When we start talking about higher CRI and lower temps its not black and white.
I have some 80 CRI XP-L i love more than some of my SST-20, but generally the SST-20 is going to give you amazing colour rendition and the ones with good tint are more readily available than a Cree.
If you think the throw is great on the SST-20, wait until you cut the dome off it, its something else all together! More throw, less green.
Lets just say my carpet has a lot of SST-20 domes in it if you looked
What’s your de-dome method if you don’t mind sharing? Slice it close with a razor blade? Do you use any washer or spacer to keep from hitting the bond wires? or do you leave the phosphor “hump” over the wires intact? Thanks a ton, I wish all leds could be de-domed as easily as old Xm-L2s with heat and a scalpel to just pop it off
I can’t find the thread super-easily, but tips have been given before. For SSTs and LH351Ds, the trick is an MCPCB without solder on it (besides attaching the LED of course) and a good reflow. Then, carefully selected washer thicknesses allowing you to shave the LED down. I’m not sure where the debate stands on multiple slices vs. one cut. Also, as a disclaimer, I haven’t done this myself - I’ve just been using TIRs with tint-shifty LEDs.
Wasn’t judging the resurrection of the thread, just the relevancy of me answering a 2 year old question as if it had just been asked
As for slicing, i’m not an expert but i done a few with washers and a razor blade that has one side covered with insulation tape for (my) safety.
I’ve done both bare LEDs and LEDs mounted on boards that have clean, flat pads so the washers sit flat on the board. For a couple of LEDs i have a couple of washers with different heights so i take the bulk of the dome off in a first slice and then refine it with a slightly lower second slice, for other LEDs i only have one washer but it seems harder to get a clean slice this way.
The size of the hole in the centre of the washer is important, too large and there’s very little stability for getting a single, clean slice, if the LED moves with the razor and the slice stops it tends to leave a bit of a ridge. In fact that hardest part for me is being able to do one clean motion without encroaching on my fingers that are holding the washer.
I have done a couple of freehand slices as well where i’ve been too lazy to prepare the LED and board, the first one i did was a beautiful slice, the next two were messy… but got the job done i think, haven’t measured anything to know how effective they were.
Next time i will try heating up the dome somehow to soften it, will hopefully make the slicing smoother.