Focusing lamps


Flashlight Enthusiast
Jul 19, 2014
Mobjack Bay
I have a lot of trouble focusing lamps. I know there was an old post that explained focusing in detail, included a cutaway diagram, but I can't seem to find it. I wish there was a sticky for focusing.

Most of my problem is not recognizing which way the lamp is unfocused, whether too deep in the reflector or too high. The remainder of my problem is the aggravation of disassembling and pulling out the socket or lamp to add or remove shims. These in combination makes for a lot of frustration.

A focused lamp is easy to recognize, because the hot spot is round, and if the beam can be seen it extends from the head parallel to it and then slightly tapers out. All my Surefire Elite heads and lamps are focused perfectly. Some Elite heads are slightly floodier with a larger hotspot, and some lamps are slightly more or less floody. I have one MN02 that produces a tiny hotspot in any Elite head, and I have one Elite head with a massive hotspot with any lamp compared to the others, but regardless, everything is always focussed on those SF Elite heads.

But with the KT4 head, due to different sized lamps and where the filiment lands, with some lamps I sometimes get an eye-shaped hotspot, and then I have no idea what to do about it, not knowing whether the lamp even can be focused to begin with. I've spent an hour at a time monkeying with shims on some lamps and never achieve satisfaction.

If anyone knows what lamp focusing post I meant and can find it, link appreciated. Or if anyone wants to rehash focusing techniques for me, very much appreciated.
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