A Perfect Dedome?

With this XM-L2 de-dome, on a lot of copper and using a Powerizer LiNiMnCo 26650 cell at 4.2V, Iā€™m seeing the following tail readings

  1. .04A
  2. .16A
  3. 1.0A
  4. 2.14A
  5. 4.22A

Works for me! :slight_smile:

Can you measure the voltage across the emitter on high? If its the same as Vb, you wonā€™t get any more current no matter how many chips you add. Need a boost/buck driver instead.

I think the DMM said 3.53V, but now that Iā€™m legally blind I canā€™t be for certain.

The emitter being on a pedestal makes that an easy reading to get, except for the looking into 1200 lumens part.

Oops, my badā€¦Matchā€™s chart says something like 1450 lumens, according to my peripheral vision. Everything else reads ā€œpurpleā€

So disappointed!! I was making my first attempt at a de-dome. I am currently in the process of modding two old lights which both used XM-L T6 Emitters. So I thought since I am not using them anymore I can practice de-doming them before buying an XP-G2 for another project.

I work at a panel and paint shop and so I thought I would give some 2K thinners a try since we have a big supply of it. It was going great until a family member thought they would be funny and made a gesture to drink from the mug I had it sitting in. The disturbance made the dome break the wires and pull some of the phosphor coating off. :frowning:

The resultā€¦

Second attempt. (I need a camera with a better macro function!!)

Pretty happy with this one, it didnā€™t get disturbed like the last one.

Would you guys say that a dodming on an XM-L or an XM-L2 would be easier? :slight_smile:

For me, the XM-L2 de-domes flawlessly, seems easier than the XML's, but haven't done an XML in quite a while.

And your macro shot is pdg to be complaining about it! How do you like it now? Did it warm up too much? Mine was pretty blue to begin with, now itā€™s much closer to white. Me Like! :slight_smile:

Great, thanks for letting me know.

How long do you dip it in gasoline?

Probably a bit longer would be better. Fresh gas, even better, just drop it in overnight and you should be good to go.

I havenā€™t actually done anything with it! It was one that I pulled out of a light which I am replacing with an XM-L2 U2 so I figured I would just use it as a practice one. I will get around to seeing how it looks in something I suppose. I really want to do a de-domed XP-G2 in an aspheric host.

Am I right in thinking if I prefer the whiter end of the neutral range I should get something like a 1C tint XP-G2 to de-dome? What sort of tint would that go to after de-dome? Like a 3C or warmer?

Also I used 2K thinners and it took about 30 mins. Didnā€™t appear to have any effect on the phosphor either.

Someone here has measured color temp before & after - I'm thinking it's got to have been texaspyro - iirc he measured about a 1200-1300K shift downwards. Quite a lot more than everybody would have guessed. For a thrower (and why else would you de-dome?) where color rendering is less important I don't think you can start with one that's too cool. 7000K would give you a de-domed result of 57-5800K or so? Still a lot warmer than typical for a dedicated thrower.

XML2 U2 '1C' with dome...

and XML2 U2 '1C' without dome...

Thanks for your reply DBCstm. I was just able to get $2 worth of gasoline and I think Iā€™m set for many many emitters.

Nice beamshots comfychair, itā€™s good to see them again. One thing I just wanted to point out was that since the C8 reflector is bigger than that of a P60, they canā€™t be used for comparing beam angles, right?

Right, color temp only. But they started as the same bin/tint LEDs from the same reel.

Awesome, thanks.

Hi,

How much gasoline do you get for $2 in Seoulā€¦. like a thimble-ful :)?

:bigsmile:

About a liter of regular gasoline. Just under a liter for premium though.

The high gas prices only affect the poor and middle class though, the rich still drive their gas guzzlers like there is no tomorrow.

Dedoming shifts XML color temps down by a factor of 0.65 to 0.75

Thats exactly the tint I want my aspheric XP-G2 to have. Thanks!