Focusing ROP w/ FM's reflector?

Who else has FM's alluminum reflector and can focus it perfectly? it might just be me. cammed/ not cammed. I'm using ROP high and the beam looks pretty uneven

any opinions?

Is it orange peel or smooth?

smooth, might have helped if i put that in OP. could it have to do w/ the diameter of the lens

I don't think lens diameter makes much of a difference, as long as it fits. A smoothe reflector will always have beam artifacts.

mine looks like a circle with a triangle above it

kinda like if you draw a fish kid style.

I had the same issue with the first ROP using a smooth reflector. See if you can work on getting the bulb as centered as possible. That helps a lot. Like has been said before, it is going to have artifacts, but yours sounds pretty bad.

yeah i've been playing w/ the bulb, my protractor is giving me 90° more or less and its still baddish.

Have a look at this easy bulb frosting thread, might be just what the doctor ordered.

jake22 -

I think I may know what's wrong by your description. This may be an opportunity for you to optimize most of your incandescent lights. Or, I don't have a clue. The second case happens more often than the first.

While wearing eye protection, not ever allowing the flashlight to be pointed at your person, you can free hand manipulate the reflector. This will need to be done in short bursts as you don't want that lamp very hot in case (and you will) you bump it with the cooler reflector. Moving the reflector up and down will let you know if the reflector is allowing the lamp to go deep enough to find correct axial focus. If it doesn't the hole may need to be widened. If it does go deep enough you can then check out the lateral (side to side) focus. This is often overlooked.

All of my HotWires have the lamps installed so that when the switch is pointed to the sky the beam pattern artifacts are wide to the left and right. This is partly because I use the shape of the beam and the different levels of intensity for the most beneficial effect. The other reason is that it makes the task of getting the lateral focus correct a little more simple.


A smooth reflector is a beautiful thing. I have several types of reflectors but I have a great affection for a beam that is populated severely with artifacts. If the artifacts are symmetrical then my little orchestra of photons is in tune and harmonic.

Using the fish comparison, if you are getting something like this

<`{{{{{{<<

a lateral adjustment is needed. What you want is the union of two fish joined at the head like this

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To adjust this PR lamp slightly bend on side of the flange up to rock the filiment to center. For the single fish above I would bend the flange on the right side upward. It may take a few tries but when its done you'll notice improved performance. Hope that helped.