But if you’re going for ultimate throw you would use LEDs like the Black Flat or CFT90 which already don’t have a dome
So there’s really no need for dedoming anymore.
Especially since the xpg3 and similar new LEDs don’t give improvement like the old xpg2 did.
There are still areas where you can’t beat dedomed emitters:
XHP70.2 offers so much output that no flat LED can compete. Especially for the price.
SST-40 is cheap and powerful and 3V. XHP35 HI is somewhat close, but way costlier and 12V which makes it sometimes infeasible.
I guess these are the biggest deals.
But also:
Luxeon MX is probably the highest output 3V LED below $100. Dedoming it seems to make sense.
XP-L W2 provides similar throw to XP-L HI, but slightly higher output. Not much though
I expect LH351D to beat XP-L for output and roughly match it for throw, further differentiating it from XP-L HI. To be precise, I expect it to be slightly floodier.
And on top of that: many flat LEDs are only available in cool white. For those who want their LEDs to be warmer, dedoming increases LED selection.
I still got some CW XP-Gs that I was going to dedome. You lose output somewhat, but gain throw by having it be a more concentrated beam.
Also, dedoming warms the beam somewhat. Albeit unpredictably, as you can end up with a lemon-yellow beam or a beam with a nasty green tint, etc.
Since Cree came out with HI LEDs (vs HD), they kind of obviated the need to dedome LEDs. And they’re already binned, so you more or less know what color/tint they’ll be.
But I have yet to see a HI version of any G chip (eg, XP-G2 HI), let alone an E or E2. If you want a flashlight laser, you can dedome an XP-E2. Not many lumens, but a pencil-beam that’ll reach quite far.
So, sure, you can “throw” more and over a wider cone of light with sheer brute force, belting out a whole order of magnitude more lumens for the same throw, but good luck with heat, battery drain, longevity, etc. Sure, a pencil-beam thrower will be quite limited in actual usage, but for that use, it’ll be unbeatable.
Well, by “dedoming” most people here mean chemical dedoming.
Dome shaving is different.
Anyone can do it and it’s a lot safer.
No tint shift, no damage to phosphor, silicone layer left on top for protection, almost the same performance as dedoming.
Wait a second. Do you mean to tell me that shadoming eliminates tint shift vs full boogie chemical dedoming?
If so, then why in hell chem dedome?
PS. Oops……
Here’s your on-topic that addresses that ? I do believe.
By Enderman……
“Also, my first hypothesis was that dedoming removes a layer of the new phosphor, but I read somewhere that there might actually be phosphor mixed INSIDE the dome material, which might be the reason it gets more lumens.
Different technique, same purpose. In my experience even with shaving domes the tint can change sometimes. I sliced my 219b 5000k’s in my s41 and they went to around 4000k.
For gas dedoming I like to start with a 3D tint to get an acceptable tint.
That topic about the XP G3 is very old, it’s already been found out that there is light emitted from the side of the die which increases the lumen output but doesn’t add to the throw.
And chemical dedoming is good if you want a perfectly clean die without the lumen decrease from dome shaving. It’s just a lot more things that can go wrong.
It sounds alright to me, koef3’s xhp70.2 topic shows ~32mm^2 of die area with the dome on.
The XHP70.2 has four 2x2mm dies so total 16mm^2, so by removing the dome you essentially cut the area down by half which would double the intensity, and then you factor in the losses and get ~80%.
I no longer dedome XPL, XML2, or XPG2. I used to dedome them in Coleman fuel. This dramatically increased their throw but gave them horrible green tint. Haven’t dedomed these emitters since XPL HI came out.