Film-Tech Forum ARCHIVE: Silly bulb mount - those crazy Kneisley Xenex's!

This is topic Silly bulb mount - those crazy Kneisley Xenex's! in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Tim Reed (Member # 137) on 11-25-2006, 10:58 AM:

What's with that anode connection? A slip collar, gripping the bulb right over the cooling holes?! What's going to keep that seal from overheating? I just replaced an LTI 3K HTP bulb in a Xenex with another bulb of the exact same model number. The new bulb has the little "positive" symbol cutouts/holes in the metal neck of the bulb, while the old bulb had long, open slots in more of a cast-metal anode. I'm really concerned for the new bulb not being cooled properly, since that Kneisley collar is covering two of the three "positive" airholes.

Also, I don't care to crank down that connection clamp on the thinner part of the bulb metal... right above the glass seal!

Why don't they just have an anode nipple cable like every other lamphouse? It's been at least 20 years since I had anything to do with Kneisley lamphouses, but I could swear I remember them having a cable connector for the anodes? Yes, no, maybe? Or, is this particular lamphouse missing a cable? No manuals on the Xenex I equipment.

EDIT: I think I've answered my own question. I did a web search and found this:

The picture clearly shows an anode cable on the end of the bulb going to the rectifier cable, which is attached to the anode support arm. I KNEW the lamphouse I was working on was missing parts! Its only + electrical connection to the bulb is through that anode support collar!

Does anyone have a part number for this cable, please? Alternately, I guess I'll try to use a bulb cable (the ones that ship attached to other models of bulbs). I'm not content to let that slip-collar carry current for the bulb, at that connection point.

[ 11-25-2006, 12:30 PM: Message edited by: Tim Reed ]

Posted by Gordon McLeod (Member # 33) on 11-25-2006, 12:25 PM:

The Xenex 1 will take almost any style of lamp existant and there is a large anount of adapter cables available
They always had a split tube to slide over the anode end for mounting and it hasn't been a cooling issue in the past with Osram or PE lamps

Posted by Tim Reed (Member # 137) on 11-25-2006, 12:28 PM:

Thanks, Gordon. [Smile]

Posted by Gordon McLeod (Member # 33) on 11-25-2006, 04:17 PM:

I would not use the anode suport to provide lamp current
I can't seem to find a list of kneisley cables and adapters

Posted by Richard Fowler (Member # 893) on 11-25-2006, 05:16 PM:

If the LTI specs is like Osram then it is L-1176 for Anode / L-1314 for Cathode for 3KW

Posted by Tim Reed (Member # 137) on 11-26-2006, 01:55 AM:

Thanks, Richard!

Posted by Monte L Fullmer (Member # 2797) on 11-26-2006, 05:03 AM:

I put in a Christie CXL-30R in a XENEX and ran the attached anode cable direct to the support arm were the positive cable is attached to and bolted the two cables together on that support arm - forget about that anode cap that is on the end of the bulb.

Bulb's been running for two years (in a drive-in) without any problems..

Posted by Louis Bornwasser (Member # 3063) on 11-26-2006, 09:44 AM:

Tim: follow Monte's advice in any metal reflector lamphouse, especially Xenex II's. The small lead supplied by Kneisley is not up to the task of carrying current while exposed to the heat from the light. Louis

Posted by Tim Reed (Member # 137) on 11-26-2006, 04:49 PM:

Thanks, Louis and Monte. It's a Xenex I with a glass reflector. I'll locate a bulb cable somewhere and just use that.

Posted by Monte L Fullmer (Member # 2797) on 11-26-2006, 06:37 PM:

...and to add since Louis mentioned a metal reflector version of this lamphouse in doing this retrofit, the XENEX that I did this retrofit does have a glass reflector.

Is there a special reasoning or precaution that I need to know where maybe this retrofit could cause problems down the road using a glass reflector?

Why I did do this retrofit is that the anode cap and cable assembly welded itself onto the old bulb since those excessively small allen setscrews in the cap have corroded beyond use within the cap. Plus, the cable itself was well into a serious state of crystalization and getting into the brittle stage.

Thx-Monte

Posted by Louis Bornwasser (Member # 3063) on 11-26-2006, 06:40 PM:

No, just needed more with the metal reflector; more light and more heating. Louis

Posted by Richard May (Member # 2627) on 11-27-2006, 09:39 AM:

I find it strange that with all the xenex lamphouses I work with, which is probably 30 or so, none of them have that cable on the end. They all use that front support to carry the current. None of them have had a bulb issue in the past.

Posted by Brad Miller (Member # 2) on 11-27-2006, 10:16 AM:

Monte, did you say a 3K at a drive in? That picture must be awful dark. [thumbsdown]

Posted by John Pytlak (Member # 331) on 11-27-2006, 10:40 AM:

quote:
Monte, did you say a 3K at a drive in? That picture must be awful dark. [thumbsdown]

Maybe suitable for a smaller screen? But I agree that 3K is going to have a hard time lighting a big drive-in screen, since most screens would have a gain much lower than 1.

Posted by Mark Gulbrandsen (Member # 72) on 11-27-2006, 11:35 AM:

quote: John Pytlak
Maybe suitable for a smaller screen? But I agree that 3K is going to have a hard time lighting a big drive-in screen, since most screens would have a gain much lower than 1.

John,
I had several D.I.'s that I serviced that only had single phase power. So till the advent of the Strong(or weak)switcher 3kw was the maximum size rectifier one could power. Of course two in parallel would also easily light a larger lamp but that typically was not done for what ever reason. One of the Single phase D.I.'s I serviced in Bass Lake, IN. got a pair of high speed movements installed so ended up with better than 4kw worth of light on screen.

Mark

Posted by Monte L Fullmer (Member # 2797) on 11-27-2006, 01:50 PM:

Screen is 45x90 with a 435 ft throw. No, there's 3ph out there, but the owner got literally suckered in a system that definitely wasn't designed for a drive-in of this size - maybe for a smaller screen and shorter throw....

Lamphouse that uesd to be out there was as ORC that ran 4200w bulbs, but heard that the rectifier went kaput, thus the owner purchased equipment out of a SMALL closed-down drive in-which included a Century SA and a BALCO platter.

Drive-in used to have one of those large reel underslung transports that the projector was mounted on a platform directly above the takeup reel. Thus, when the rectifer went, the main operator out there 'conned' the owner to buy this other booth so he wouldn't have to fuss with film rewinding...

The rectifier is also a Kneisley but the smaller model with maximum current output of only 95 amps being attached to this XENEX I

What's real bad also is the screen faces eastward, making those sunset starts horrible being of the lesser wattage bulb (and having a Century with no water cooling to allow higher wattage bulbs - that was also purchased in that sucker deal...). I've set the taps on that rectifier as high as I dare go to get decent light out to that screen (and on scope using B&L CS attachment I with a 5.97inch backup)

When I started to service this drive-in (and do some shifts out there as well..), light output was horrible due to the OSRAM that was in there was almost burnt up-mainly due to that anode cap was all but black, allen set screws were all corroded in, and the cable was almost crystallized and brittle. Thus, knowing that I couldn't get that cap off and no parts floating around for that XENEX, was the easy choice of just getting a bulb with the attached anode cable and do the direct connection as posted above.

With this conversion, I managed to get a little bit of better light out of the thing, but still a far cry of what a 4200w bulb would fire out through that Century.

Yeah, I fully agree though with the illumination factor..

-Monte

Posted by Dave Bird (Member # 490) on 11-28-2006, 01:05 PM:

So long as the i's get dotted and t's crossed, my family and I will be operating a drive-in in eastern Ontario next summer that currently runs with a similar setup to the one Monte describes above. I nearly bought the place 5 years ago during a 2-year closure and at the time, the booth housed those big, beautiful gold Gaumont-Kalee's with Strong 135 3-ph. arclamps (still 3 or 4 of 'em there).

The big eastern ice storm occurred during the closure, and though 3-phase power runs right past the building, the Hydro utility plucked the transformers for emergency use elsewhere. A long-time former employee of the drive-in's founder came along and re-opened in 2000, and Hydro was very reluctant to replace the service it had pilfered.

So now as we sit, we're looking at about 425 ft. to an 80-foot screen - Balco 5-deck platter running to an XL with Xenex lamphouse and - wait for it - TWO K bulb! Oh, and a Jaxlight.

I spent about 8 weekends there this past summer figuring out how everything that's there now ticks. The mission come spring is "clean it up, fix it up, and improve". I'm not satisfied with the brightness for 'Scope and it goes without saying, if we're upping the wattage for 'Scope, then Flat will follow. But believe it or not, the Flat images are decent, clear and brightness comparable to many of the other drive-ins around who mostly use 3K on 50-60 foot screens.

As a side note, this lamphouse apparently received the much-debated "Technalite" treatment at time of install.

I'd be interested to hear some suggestions on both intermediate steps with this lamphouse, as well as some more permanent suggestions. Realistically, when I go back in the spring to open, I'd like to do some "instant" upgrades (like a 3K lamp) to improve until we can get the proper things done, like 3-phase power and a bigger lamphouse, etc.

Posted by Monte L Fullmer (Member # 2797) on 11-28-2006, 03:15 PM:

quote: Dave Bird
Oh, and a Jaxlight.

*cough* .. *cough* [Eek!]

Get a BACP reverse reader immediately and get rid of that Jaxlight to give to your worst competition there.

Yea, you definitely need some more horsepower to hit that size of screen with that long throw...2k bulb on a 80ft screen at 400 plus feet?? What were they thinking?

Posted by Louis Bornwasser (Member # 3063) on 11-28-2006, 06:38 PM:

There might be an intermediate step. IF the flat is OK and the scope is bad; then new scope lenses will make a big improvement in the scope. (scope should be 150% brighter than flat) You will want to do this later anyway.

As for xenon horsepower; if you can find any single phase rectifiers, you can gang them up to whatever power you need including 6k. I am not impressed with anyone's switcher rectifier. Louis

Posted by Jack Ondracek (Member # 1466) on 11-28-2006, 07:51 PM:

Hope you took some notes when you were down here, Dave. [Cool]

Posted by Tim Reed (Member # 137) on 11-28-2006, 07:57 PM:

quote: Monte L Fullmer
to hit that size of screen with that long throw

FWIW, the throw doesn't matter, except in regards to requiring longer, and possibly, slower lenses. All else remaining the same, the screen could be 1,000 ft. away and yield the same results.

[Smile]

Posted by Sam D. Chavez (Member # 1841) on 11-28-2006, 08:22 PM:

Thank you Brother Tim. I pointed this out for almost 40 years until I got tired of "explaining" this.

If you were to measure the light arriving at the screen, it would be the same whether its 40 Ft. or 400 ft., except for the possible loss inside the lens.

Posted by Monte L Fullmer (Member # 2797) on 11-28-2006, 08:59 PM:

Thx on this explanation about throws and lenses (slow, or fast and was really never explained in this area of projection)which - and don't mean to drift off topic here, yet it really isn't since we're picking on XENEX lamphouses and to get light to the screen at a certain brightness so one can see the picture here - how can one tell if his optics are indeed slow to getting the light out there to where replacement faster lenses are needed..?

thx-Monte

Posted by Dave Bird (Member # 490) on 11-28-2006, 10:23 PM:

Darn right I was Jack, mental notes anyway. I think there are probably alot of top notch setups, especially among those on boards like this, but I've never seen systems as good as yours. Ticketing, Concessions, Projection, the whole operation just as smooth as silk. We hope to get back down that way in the spring.

Thanks for the answers folks, this should be alot of fun, in fact, I don't think we'd be doing it if there WEREN'T things to be done.

What were they thinking? Well, the owner's a great guy, worked there for many years and despite having too many things to do already, just couldn't stand to see her closed. Got hamstrung when the 3ph. service was pulled out, wasn't sure he'd make any money at it, so did what he had to I suppose.

Really unique place, runs almost predominantly family movies with a more mature second feature all summer, and does very well. We agree that it needs a couple more screens and a much enhanced concession (my expertise). But I'm also a bit of a gear-head, and I'm looking forward to wow-ing the crowd with more light and better sound. And that's more than he'd like to tackle at this point. It's a throwback, of course, even the box office reports are pecked out on a typewriter, and needs a splash of paint here and there. But it was built like a bomb shelter, best of the best back in '53, so it will look very, very good when we're done with it.

Posted by Tim Reed (Member # 137) on 11-29-2006, 04:14 AM:

quote: Monte L Fullmer
how can one tell if his optics are indeed slow to getting the light out there to where replacement faster lenses are needed..?

Monte, "slow" or "fast" refers to the aperture of the lens, or, how efficient a particular lens is at passing the cone of light. A slow lens has a high f-stop, e.g., f/4. A fast lens would be like an f/1.8. It is related to the focal length and the diameter of the lens.

When you get into an exceptionally high focal length lenses, the angle of light they will pass gets narrower and narrower, resulting in higher effective f-stop values. This cuts the available light.

The upside is, with higher f-stops, the depth of field also increases, so it's easier to keep the image focused. The converse is also true.

Posted by Louis Bornwasser (Member # 3063) on 11-29-2006, 11:12 AM:

Sam, I am so tired of trying to kill this "long throw" issue, that I won't even respond to it anymore.........of course, you COULD factor in fog, air pollution or low flying aircraft. Louis

Posted by Monte L Fullmer (Member # 2797) on 11-29-2006, 02:32 PM:

Thx for this info Tim, for was never taught this.

So, basically, if the lenses were removed out of the machine, then throw the light on the screen, the illumination would be the same then. But, whatever kind of lens goes into the machine it has the properties of presenting either a good picture, or a dim picture.

So, possibly in the case of this drive-in that I service: The flat is a f/3.50 and the scope is the f/5.97 elements. I've always wonder why the flat is so much easier to focus and keeps the good focus in as well as a better picture than the scope lens would emit.

But, also stated above, that the scope needs to be the better picture due to the larger opening of the aperture. Thus, do we need to just get more light out through that longer lens?

thx-Monte

Posted by Scott Norwood (Member # 30) on 11-29-2006, 03:28 PM:

Those sound like focal lengths (i.e. 3.5" and 5.97"), not lens speeds. Most cinema lenses seem to be somewhere in the f/1.7 to f/2.0 range. Switching from an f/2 lens to an f/4 lens would cut the light output by half (one stop) and would mean the difference between 16fl and 8fl on screen (everything else being equal).

Question: does an anamorphic adapter change the effective speed of the prime lens?

Posted by Monte L Fullmer (Member # 2797) on 11-29-2006, 03:33 PM:

OH...sorry on this ..yes, these are focal lengths not aperture opening sizes...my bad...

Yes, the flat lens has a huge aperture opening (like over a f/2 or something-lens having almost the same outside diameter as with the barrel diameter) whereas the scope has a smaller (can't remember the opening) than the flat lens has...(you'd think that the scope backup should have the larger aperture opening...)

thx for clearing this up for me....learn something new in here.

-Monte

Posted by Gordon McLeod (Member # 33) on 11-30-2006, 07:10 PM:

Dave would that be the napanee drivein by any chance?

Posted by Dave Bird (Member # 490) on 12-01-2006, 10:03 AM:

No Gordon, Perth. In fact, from our old family cottage, I'll be driving past your antique emporium on the way up to Hwy. 7 during the "weekends only" season...