I abandoned the base when we closed the theater and dismantled the booth. It promptly went into the dumpster along with a broken LL-1 that was dropped when removed from the Lido Theater in Mount Vernon before Plitt went bankrupt. The LL-1 was so heavy I had to take a sledge hammer and make a bunch of little LL-1's out of it so it could be moved. That was before I figured out how to dismantle it into manageable chunks.

I've never had such trouble with the carbons -- maybe the optical system of the carbon lamphouse is more forgiving of slight optical misalignments? Anyway, with all the great tips the guys here have been posting, it becomes pretty obvious to me that these tips didn't come from a Strong lamphouse manual. None of this stuff seems like it is part of the lamphouse design. Seems like they could design some of this alignment minutia into the lamphouse itself to make setting the things up reliant a little less on years of personal experience and a little more on well placed, intuitive knobs and adjustment screws.

Frank

dave macaulay , i tried to email you, but your email address doesn't seem to be working? , just wanted to say thanks!

Working Distance is the measurement from the film plane to some reference point of the reflector -- with Strong equipment, that's from the hole in the reflector to the film plane, and for Super Lume-X 11" reflector that WD should be about 25-3/4 inches to the aperture plate.

Once WD is correct, then you need to get the reflector on the same optical axis as the lens. The laser is a great tool for this and centers up the reflector really well. The string simulates the laser and does a nice job to show you what the reflector's optical surface is actually doing.

Once this primary reflector alignment is complete, then it's getting the bulb in the right place. This is generally pretty easy using the focus controls of the lamphouse, assuming the anode (POS) support is in the right place. Lamps from 700-1600 watts all use an anode adaptor in the Super Lume-X, so that should be the highest adjustment point of the anode support for all those lamps. For 2kw and above, the anode of the lamp itself is supported so it needs to accommodate the varying ferrule diameters of the xenon lamp manufacturers -- and they vary quite a bit depending on seal designs and such. I usually adjust that anode support just as I look at the string alignment -- get a viewing angle looking at the front end of the lamp on the reflector's surface, and adjust the height so the anode "covers" its image on the reflector. That will get you close enough that the focus control can make any fine adjustments required -- there's LOTS of adjustment room there.

Looking at the light on screen without the lens tells you a lot too. The black rings mentioned before (good post, by the way) should be circular and generally concentric. Anything resembling a "figure 8" means the reflector got whacked or is really deformed -- chances are pretty good the light's poor on screen.

Brad -- I took a quick look through this thread and did not see if you did try the string alignment just to see where things sit. The string is a quick way to see if the reflector is actually aligned where you think it is. Ideally you'd use a laser first, but the string might help a bit IF you feel the primary alignmemnt of the lamphouse is not correct. It sounds like you are closer to proper alignment though.

Even the old cast iron bases generally had some method of adjustment. If the lamp table really doesn't move, chances are there are provisions for adjusting the location of the soundhead & projector, even if it was just loosening the bolts and moving it.

Carbon arc optics are more forgiving, yes. Take a look at the arc flame -- it's HUGE compared to the plasma ball of a xenon lamp. Reflectors were generally very "slow" optically -- you see that in the shallowness of their curves. Xenon optics are totally different, based on maximum collection of light from that relatively small plasma ball of the lamp. They are also "faster", usually f2.1 or less. So yes, alignment of the xenon system is probably more critical, but their performance potential is also higher if properly aligned.

Early xenon optical systems had some "adjustment on the fly" provisions for the reflector built into them, but that proved to be more trouble in the long run. In the 70's the two-piece lamphouses, such as the Super Lume-X and virtually all others, fixed the reflector in place. The theory was -- and still is -- that if primary alignment of the system was done correctly, it never again needed adjustment. Properly aligned, these lamhouses could put out a great, even field of light.

If there were no other provisions on the pedestal for alignment, it wasn't unusual to shim as required. That was usually getting the lamphouse "up" a little, as the Super Lume-X was designed to be just short of the 9-1/2" optical height standard the industry had settled on.

Phew -- time for that third cup of coffee...

Pat

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