U2 donut hole?

So tell me about the U2 donut hole, do they all have them? Is it annoying? Does it disappear at some point from the light, is it only a close up phenomena?

How about the consistency of tint?

Bill

My U2 has a slight donut hole if I'm looking at white walls only .... :shrug:
During general use I don't even notice it. From what I've read on
the forum most people do not have a problem with it, however
some do ........

What Pwdrkeg said. Mine had a slight donut hole as well. Not that big of a deal - really.

Will

Agreed, walls only, not noticable in real world environments, with the exception of snow.

-PSM

Tint problems?


Bill

Bill

My first U2 had no donut hole at all. If it had one I was never sure I could see it even if I was wall hunting.

That U2 had a great emitter color too, very white. But alas, the dimmer did not work from the day I received it. I loved the light so much I kept it broken for 6 months but eventually I sent it back.

My replacement U2 from SF has a donut hole so pronounced I did not believe my eyes when I first turned it on. It is even distracting when using the light for normal use.

When I get the time, I plan to take it apart and replace the emitter and adjust the focus.

Cheers
Dave

My U2 also has a very pronounced hole. It's even noticable in 'normal' use, so it does get a little irritating sometimes. Still a great torch though!

I have been planning to make a machined tool/fixture to unscrew the head and bezel.

Dave

When the donut hole issue first came up, I pulled out my U2 to see what it was all about. I wondered if I had been missing something. No, mine does have a barely perceptible hole in the center of the hotspot. If I shine my light in a dark room at the white wall, I can just see a faint area.

Luck of the draw I guess. But why?

Is the donut hole caused by something in the LED die itself or by the physical mounting of the LED in relation to the hole in the reflector?

Whatever the cause, why should there be this much variation. I realize that like tint, this hole will bother some people way more than others.

It seems to me (and I'll bet to many others), that there should be more consistency in a light in this price range and from this manufacturer.

While my U2 is nearly perfect in beam quality and tint, the "white" LEDs in my A2 are so blue it's distracting.

I am not overly fussy, but I guess I just have higher expectations when buying top of the line. I think that is perfectly reasonable.

Mark

The donut hole in my U2 is more pronounced on low settings, but it's quite visible on all. Shining it around the house it's usually noticeable on walls/curtains. Outside it's less noticeable. It's not bad enough to make me send it in to SureFire for warranty work.

Oh yeah, the tint. It's quite white, only my Gladius is whiter, and slightly so. And the Gladius color is so pure it's divine! Lower levels of the U2 it's slightly green, but still real white.

Wow! I was upset because a $20 light had a hole!

If I spent THAT kind of coin on a Surefire, I'd be FURIOUS!

The donut hole is inevitable unless you have a big or very deep reflector, my real question was more about how much and how noticeable.

Tint is a big issue also.

Bill

my original u2 had a very noticeable dark spot/donut hole and i called and talked to a techie at SF. He didn't say it was a flaw but he did ask me to send it back. I did and now my u2 is donut hole free. But I did get a light back with a bit of a violet tint. My original was whiter... Go figure. It would be nice if this model had better consistency IMO.

The U2 I just had as part of the passaround has a slight donut hole. It's more visible on low and while shining the light onto a wall. I took it outside for a "ride", and I couldn't find the hole, even after looking for it; it's just not there.

Tint? What tint? This thing's WHITE. Oh, yeah, and did someone say BRIGHT too?! Forget the L4, I want a U2 now.

Mine had a pretty noticeable donut--easy to detect on a wall and most noticeable at lower output levels. I am convinced that it is caused by the emitter itself. At very close distances--like two inches or so--you can plainly see the shadow of the emitter on a flat surface. Mine also had a sickly green tint--noticeable even without direct comparison to other lights.

I called up Surefire and asked for an RMA. They agreed that it wasn't normal behaviour and asked me to send it back. I just received my repaired U2 on Tuesday of this week. Two week turn around time including shipping was actually pretty good.

The new head still has a donut, though less of one. The color is much better, but it still has a bluish tint with just a touch of green at lower output levels. I like this head much better, but it's definitely not perfect. From my own experience and from what others have said, the only way to completely remove the donut is to defocus the emitter slightly thus reducing throw. Since I can't see the donut any more unless I am looking for it on a flat surface, I'm not going to make a change.

- Jared

That REEKS! Glad I can't afford one as I would SURELY be upset!

The dognut holes on my Lux V Surefires are all very minor to not noticable. On white walls, I usually have to really look for them to see them a very minor non-issue my opinion says. No worries, you'll like the U2, excellent beam and very useful.