6x22 lens train issues

I’m currently working on two 6x22 Altman 360Q lens trains. Find it curious on both examples I have that the lens retaining rings are way short of the dimple in the lens train front from where they should be. Like a quarter inch difference between where the lens retaining ring and where the dimples are.

Realize that the 6x16 has two lenses, and the 6x22 has one and this missing lens might be that quarter inch of space problem.... perhaps I have 6x16 fronts in 6x22 barrels as a possibility - it is the bone yard of the inventory of extra parts.

Went to the Altman website and looked into it further and found the same lens spacer part between lenses or between standoff and lens listed. Not a different spacer in use.

Really gotta measure where the dimples are and measure the bone yard stock for surplus lenses so as to find the correct ones for the retaining ring dimples? This assuming they are somewhere in that sock?

Assuming the 6x22 lens train barrel used a 6x16 lens train assembly (big assumption) with the same spacer - only missing one lens, different dimple locations so as to retain the lens retainer, is it different parts or is it feasible to re-dimple the lens train for the now back by 1/4" lens so as to better support the placement of the lens retainer? Can’t imagine why I would have some seemingly 6x16 lens trains in a 6x22 lens train plus snout fixture but apparently I do as the dimples don’t lock the lens in at the proper position short of the second lens the 6x22 don’t have.

Anyone more familiar with a 6x22 in perhaps measuring the length of the lens train and length from front or rear for these dimples I could search for? Thinking I have 6x16 lens trains with one lens removed so far in my 6x22 lens train with snout fixtures and that’s a problem as the lens retainer don’t align with the dimples so as to keep the lenses accurate.

More info and detailed info if at all possible in thanks. Worked with lots of them in the past, never seen this problem before but it is the bone yard and who knows who did what in the past with this say 25 year old bone yard of parts.

P.S. While I'm told Altman didn't really list dates of when the 360 came out, or when the 65 went black, this or the 360Q went black... my rep. from Altman is working on it. Will post such info in pooling themselves for specific info once I get it. It's of historic value. Will further follow up with as above center mounted clutch break as opposed to clutch cam assemblies, on the 6x22, when did they go clutch break in deveopment as perhaps another concept in dating their fixtures more specifically. Got for the museum one body with clutch break I'm going to make into a 6x16, the rest including these 6x22 are clutch cam in assembly thus earlier even if both black. Gonna need more clutch cam's, hopefully Altman or Hub has them.

Ship, did you ever figure this one out?
I started my upgrade activities with a 6x22 last night and shot it at my convenient 10' bench focus soffit and got this immculate image of the lamp and reflector. All I had done was pull the lens, clean it, and reinstall it in the proper orientation. After checking that I had done nothing dumb, it was the correct lens, etc I swung the fixture down into the room and discovered a lovely flat beam of light that looked great about 50 feet away. But any closer and now I could see some reflector facets showing up. I did check that the lens spacer is indeed indentical to all the others and you are right....there is nothing to take up that 1/4".

This is certainly a bit of a goofier fixture.
Can you only bench focus a 6x22 at 40' or so? I mean, this is absolutely amazing for lamp centering but that's not my goal here... Do I throw a piece of R119 in?

Edit: Anyone have a better way of removing the lens ring than channel-locks? I am very practiced with them and have never chipped a lens, but I don't ever get warm fuzzies with that operation...

JMBrowne said:

Edit: Anyone have a better way of removing the lens ring than channel-locks? I am very practiced with them and have never chipped a lens, but I don't ever get warm fuzzies with that operation...

Click to expand...

Rocco Wrench, aka "lens ring wrench." See wiki link. Long discontinued--I don't know where one would find one today, except in the well-appointed toolbox of an elderly stage electrician.

Long time since I worked on such a fixture. No never any advice. Your photo is interesting, segmented reflector? Was off line discussing with someone stippled reflectors with various lamp problems recently. He related that his TD noted that certain lamp filaments would not work well with certain segmented reflectors. Interesting.

A PAR Can lamp retaining ring if what I remember could work as a spacer. Steel PAR 64 lamp retaining ring would work better. Believe I for that project bent some rings of rod on my own in making it work

I share your concern in chipping a lens. Don't use Channel Loc's or perhaps pad them with e-tape if there is not a bent part of the ring to grip on. There is Channel Loc insulators on the market also. A E-taped screw driver to spead the ring from the lamp and Duck Bill Pliers to remove as a concept though the E-Tape isn't really needed.
Too bad remote, could demo in a minute this question.

ship said:

Long time since I worked on such a fixture. No never any advice. Your photo is interesting, segmented reflector? Was off line discussing with someone stippled reflectors with various lamp problems recently. He related that his TD noted that certain lamp filaments would not work well with certain segmented reflectors. Interesting.

A PAR Can lamp retaining ring if what I remember could work as a spacer. Steel PAR 64 lamp retaining ring would work better. Believe I for that project bent some rings of rod on my own in making it work

I share your concern in chipping a lens. Don't use Channel Loc's or perhaps pad them with e-tape if there is not a bent part of the ring to grip on. There is Channel Loc insulators on the market also. A E-taped screw driver to spead the ring from the lamp and Duck Bill Pliers to remove as a concept though the E-Tape isn't really needed.
Too bad remote, could demo in a minute this question.

Click to expand...

It was you and I having the discussion about reflector geometry and filament geometry and a previous TD's opinions on it. Which are not entirely crazy from a purely physics perspective. I mean, at some point it ought to matter, even if just in efficiency.
This reflector is not stippled, but it is a "Super Reflector". Not a 2nd gen faceted reflector with the smooth secondary, but the faceted reflector with I think twice the number of facets, the stepped secondary, and a slightly bluish look, which I find interesting given that these were supposedly just polished aluminum. But no, it is is ever so slightly bluish.

Like I said, when I swung this fixture down from the surface 10' away it was pointed at, it was a beautifully flat beam across the room, which I expected given that I had set the lamp depth based on a series of measurements on another fixture.

But today I realized, why not simply take a harbor freight set of channel locks and grind a groove in the jaws? Really the issue is the ring slipping out of them, otherwise they work a charm for doing lens rings.

But I think 6x22's just have a minimum distance where the beam "features" have not yet spread out enough to blend together. Which is interesting. But they must have SOME major optical difference from the rest given that a lens is missing from the optical path.

JMBrowne said:

Edit: Anyone have a better way of removing the lens ring than channel-locks? I am very practiced with them and have never chipped a lens, but I don't ever get warm fuzzies with that operation...

Click to expand...

There are a lot of "soft jaw" pliers on the market for various uses. Some with semi-permanent jaws that can be replaced if damaged. And others that are just caps that cover the jaws of a normal set of pliers.

JMBrowne said:

But they must have SOME major optical difference from the rest given that a lens is missing from the optical path.

Click to expand...

Old-school ERSs need two lenses in order to achieve a shorter EFL with thinner lenses. I.e., the EFL of a dual 6x16 fixture is 8 inches.

For a two-lens system: EFL= (f1*f2)/(f1+f2-d), where EFL=Effective Focal Length, f1=Focal Length of Lens1, f2=Focal Length of Lens2, d=Distance between Lenses.

Click to expand...

derekleffew said:

Old-school ERSs need two lenses in order to achieve a shorter EFL with thinner lenses. I.e., the EFL of a dual 6x16 fixture is 8 inches.

Click to expand...

Agree, but the 6x22 only uses one. I think I'll throw a second one in today just to see what happens. But if you look at an Altman parts list, the 6x22 uses a single 6x16 lens.

I've thought about soft-jaw pliers, sure. I was just wondering if there were any other tricks.

derekleffew said:

Rocco Wrench, aka "lens ring wrench." See wiki link. Long discontinued--I don't know where one would find one today, except in the well-appointed toolbox of an elderly stage electrician.

Click to expand...

Oh god, am I elderly now?

These have a notch in the tip that might work, someone else buy them and let me know.

I cannot explain for Altman having punched for lens ring retainers in the wrong place in going back. Dual ring best option short of fabricating a dimple tool. Also have not much looked into reflector differences in something that I am not aware of in coming up before. I have no active fixtures to work on of this type other than restored and in museum, Interested but not diving deeper into it. On the other hand, should you need 6x16 lenses... I have a large box full of them if you want to pay shipping for any of in PM.

ship said:

I cannot explain for Altman having punched for lens ring retainers in the wrong place in going back. Dual ring best option short of fabricating a dimple tool. Also have not much looked into reflector differences in something that I am not aware of in coming up before. I have no active fixtures to work on of this type other than restored and in museum, Interested but not diving deeper into it. On the other hand, should you need 6x16 lenses... I have a large box full of them if you want to pay shipping for any of in PM.

Click to expand...

I might take you up on that.

I showed another one of our good local lighting guys that 6x22 reflector pattern and focus issue and he was similarly intrigued. It is an FLK lamp in a 2nd gen faceted reflector. I spent the last few days building him some nice specials of other sizes and haven't gotten back to my 6x22 SR upgrade project. If I through a C-13D lamp into it and get a better, or even just different, pattern I will be sure to share the pictures with the group.

I like our little historic theater as it affords me the time and space to play with such things.

I installed a Super Reflector into one of our 6x22's with an FLK lamp and placed it below a 6x22 with a standard reflector and GLC lamp. Both had cleaned optics trains, in good working order, and were on a two-fer into an edison outlet. Thought the tungsten connoisseurs would find my results interesting. R114 diffusion used to give me somewhere to stick my phone and its uncalibrated light sensor.

Both of these beams were focused sharp and appeared flat on the plaster-line wall. Note the color temperature difference.

Your experiments peeked my interest, so I went to search up the lamps and this thread popped up in my browser's address bar: https://www.controlbooth.com/threads/fel-and-flk.1629/post-16448 and based on this post you should be testing with the GL series lamps in the SuperReflector 360q and the FLK in the standard one.

Hope this helps, and do keep sharing your testing!

So he is actually our former tech director and the guy I learned the most about lighting from other than ship. It is that theater that I'm performing these tests in. And, I actually have all of our current stock of Super Reflector fixtures lamped with GLC's based on Dave's reasoning.

BUT....I have come across other opinions suggesting that the FLK is designed more recently than the G series to be even more of a point source and is more efficient with the much smaller facets of a Super Reflector, while the G series, with its rectangular filament array, is possibly more closely matched to the larger traditional facets.

The problem is, both of these opinions make some sense. It is my understanding, however, that no lamp companies have ever really tested these theories. The S4 changed the industry so fast that suddenly reflector facets and filament geometry specifics were not anyone's priority.

Now, I am a data slut. A proud data slut. I am currently researching building my own test rig based on Labview integration with an excellent optical sensor and see what the truth really is. Our theater in Derry is as good as lab as any, because at the very least, my test subjects get moved into our fixture stock in excellent bench focus.

To answer your question directly, if you notice my test data, I did swap lamps, and the GLC performs marginally better in the SR but the FLK is better in both. My picture showing the FLK in the standard reflector and GLC in the Super Reflector is too over-exposed to show next to the above shot, but it was clear that the FLK was the superior lamp in either reflector, and the GLC performed slightly better in a standard reflector than it did in the Super Reflector based on uncalibrated phone light sensor readings.

So, as of right now, my semi-rigorous testing appears to show that the theory that the larger, rectangular filament array of a G series is better matched to a standard reflector, but the point source behavior of the FLK is delivering the best performance.
The caveats are that I need to run both lamps through a range of depths to truly find where each filament geometry is most efficiently located axially in the fixture. THEN I need to run through several lamps and plot the data box-and-whisker style because lamps are not created equal.

And why am I doing all of this? What else could possibly be more interesting??? I am really intrigued by this.