Curious:  How many here still dedome?

Enderman · 2018-05-18T21:27:39.000Z

Geuzzz:

Dedoming does not improve output, just increases the throw. So if you are going for ultimate throw it still makes the difference.

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.

Geuzzz · 2018-05-18T21:39:49.000Z

Enderman:

Geuzzz:

Dedoming does not improve output, just increases the throw. So if you are going for ultimate throw it still makes the difference.

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.

The xhp70.2 of VOB went from 500+kcd to 900+kcd with a reduced lumens of only 6000 over 6700 domed. Sounds like a good reason to me :sunglasses:

Agro · 2018-05-18T22:06:28.000Z

Enderman:

Geuzzz:

Dedoming does not improve output, just increases the throw. So if you are going for ultimate throw it still makes the difference.

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.

Lexel · 2018-05-19T00:30:37.000Z

chadvone · 2018-05-19T00:40:24.000Z

I haven’t found the need lately. It was fun when I was chasing numbers. These days I am happier with a smooth beam of usable light.

Enderman · 2018-05-19T00:53:07.000Z

Geuzzz:

The xhp70.2 of VOB went from 500+kcd to 900+kcd with a reduced lumens of only 6000 over 6700 domed. Sounds like a good reason to me :sunglasses:

Did he dedome it or just shave it?
Shaving it is far easier and safer, which is what most people have done.

nottawhackjob · 2018-05-19T01:47:20.000Z

Should we be using a new term to describe shaving a dome vs dedomed?

Maybe shadome?

I’ve completely dedomed many an LED but I’ve never had to shave one - of course I haven’t bought the new really expensive LEDs either.

I gather that in cases like the xhp the gain by completely dedoming vs shadoming must be pretty negligible considering the cost if you mess it up.

Lightbringer · 2018-05-19T02:35:15.000Z

What they said…

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.

nottawhackjob · 2018-05-19T05:17:19.000Z

First time I’ve read this particular thread on testing the Black Flat.

Good info indeed.

LED test / review - OSRAM OSLON Black Flat HWQP - still highest luminance of all LEDs to date! Flashlight Modding and DIY Parts

LED test / review EN Osram Oslon Black Flat HWQP LUW HWQP-8M7N-ebvF46fcbB4 UPDATE --- 06/23/18 --- raw data added! (link) Since several months this LED is a well-known and popular choice for ultra-long range distance flashlights (throwers). Many performance values are already known from other users / tests, but with this test / review I want give you and all these who want to start a project with this very interesting LED the opportunity to check all values and importan…

Geuzzz · 2018-05-19T05:52:45.000Z

Enderman:

Geuzzz:

The xhp70.2 of VOB went from 500+kcd to 900+kcd with a reduced lumens of only 6000 over 6700 domed. Sounds like a good reason to me :sunglasses:

Did he dedome it or just shave it?
Shaving it is far easier and safer, which is what most people have done.

He dedomed it by shaving the dome off

nottawhackjob · 2018-05-19T06:09:08.000Z

How much shaving do you need to consider it equal to dedomed? Norelco close or just BIC disposable shave close?

I know these are hairy questions.

Enderman · 2018-05-19T06:33:30.000Z

Geuzzz:

He dedomed it by shaving the dome off

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.

nottawhackjob · 2018-05-19T06:54:48.000Z

VOB and Texas Ace rock!!!

Great work guys.

nottawhackjob · 2018-05-19T07:13:09.000Z

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.

Dedomed LED Tints Compared: XP-G3, XP-G2, XP-L Flashlight Modding and DIY Parts

While having multiple dedomed LEDs installed right now in the same host configuration, I wanted to make a comparison of their tints. I will add more photos as they become available. The host is the OLight M3XS-UT Javelot, designed with a factory dedomed XP-L (that was known for a greenish tint), making right around 240-250kcd. LEDs shown other than factory are currently: dedomed XP-L V6 0D, dedomed XP-L V6 3D, XP-L HI V2 1A, dedomed XP-G2 S2 1A, and the most anticipated, dedomed XP-G3 S5 3A. W…

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.

Will have to test to find out…”

That hypothesis is interesting.

Geuzzz · 2018-05-19T07:09:37.000Z

Enderman:

Geuzzz:

He dedomed it by shaving the dome off

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.

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.

nottawhackjob · 2018-05-19T07:22:06.000Z

Geuzzz said……

“The xhp70.2 of VOB went from 500+kcd to 900+kcd with a reduced lumens of only 6000 over 6700 domed. Sounds like a good reason to me”

That’s an 80% increase over stock domed. Is that independently confirmed accurate??

If it is, it’s amazing. :exclamation:

Agro · 2018-05-19T07:43:45.000Z

nottawhackjob:

Geuzzz said……

“The xhp70.2 of VOB went from 500+kcd to 900+kcd with a reduced lumens of only 6000 over 6700 domed. Sounds like a good reason to me”

That’s an 80% increase over stock domed. Is that independently confirmed accurate??

If it is, it’s amazing. :exclamation:

That’s not unusual.

Enderman · 2018-05-19T09:24:18.000Z

nottawhackjob:

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?

That hypothesis is interesting.

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.

nottawhackjob:

Geuzzz said……

“The xhp70.2 of VOB went from 500+kcd to 900+kcd with a reduced lumens of only 6000 over 6700 domed. Sounds like a good reason to me”

That’s an 80% increase over stock domed. Is that independently confirmed accurate??

If it is, it’s amazing. :exclamation:

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%.

nottawhackjob · 2018-05-19T14:47:48.000Z

Thanks. I’m too used to single die emitters. :person_facepalming:

Firelight2 · 2018-05-19T16:37:55.000Z

I still occasionally slice-dedome SST40s.

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.