stage lights & bulbs

The newer PAR cans do not have an access hole in the back, the code requirements require this to be closed off to stop peopole reaching in and getting an electric shock

Depends on who you talk to in this... Kupo comes in their rock and roll cans with this screen and they sell a really cool spinning knob.

Other brands such as TMB still have the hole open.

It's not a NEC/Code issue, it's a UL listing of the fixture issue. UL I believe changed the standard a few years after one but before another.

On old steel stage PAR 64 fixtures, the testing by UL would tend to pre-date this necessity.

Also those older will find it almost funny at this point if they really read the response to "headlight" bulb...

We know that say the PAR 56 started it's life as a car headlight, but those that have a modern car are using something more like the lamps we use in or Lekos or Fresnels than an actual PAR lamp. I never had a car that had an actual round PAR lamp but had some over the years that had rectangular ones. My current and most since all have Leko like lamps, yet if I were discussing lamps, I'm not sure I would think it like a car lamp - instead a car lamp for me is the say PAR 56 used on something like a 56' Chevy...
 
My VW has par lamps.:mrgreen:
 
As long as we are way off topic and waiting for our buddy to check back in with pictures for us to identify...

I keep a couple boxes of those little medical alcohol pads around... like they use to wipe your arm before the shot. You can buy a box of 100 for like $2. Every time I open an instrument for any reason, the last thing I do is wipe the lamp off with a swab just in case. It seems like a good thing to do and I'm amazed at how much dirt comes off lamps. I even open them up once a year and give them a wipe down. It seems to have a positive effect. But I don't have that much inventory to really have a good sample size to see if it's working. Curious what some of you guys who deal with a lot of gear think of the idea.
 
As long as we are way off topic and waiting for our buddy to check back in with pictures for us to identify...

I keep a couple boxes of those little medical alcohol pads around... like they use to wipe your arm before the shot. You can buy a box of 100 for like $2. Every time I open an instrument for any reason, the last thing I do is wipe the lamp off with a swab just in case. It seems like a good thing to do and I'm amazed at how much dirt comes off lamps. I even open them up once a year and give them a wipe down. It seems to have a positive effect. But I don't have that much inventory to really have a good sample size to see if it's working. Curious what some of you guys who deal with a lot of gear think of the idea.

Thata a good idea, though with "real" Par lamps not a necessity as the envelope is housed inside the big glass lens reflector unit. At Hollywood we always kept Alcohol soaked rags for lamp/reflector cleaning.
 
I'm back... I really appreciate all of the messages while you were waiting for me with my information. I haven't been able to get pictures of the various lights, but I did find our Fresnel and PAR lights. I found information on one of the old Fresnels that is not in use: 120VAC-15A, LAMP MAX 120V 500W. The PAR that is not in use is cracked and broken, so I couldn't take measurements. I did find this information on it: 1000W 120V. The lamps we have been using in the Fresnel are: DNW 120V 500W. The lamps for the PARs are: PAR 64 LAMP 1000W 120V. I see that the numbers match, so the suggestion of being handled without gloves makes sense. I know people haven't worn gloves to change the lamps in the past, but that is going to change now that I know about doing that.

We also have some other lamps that must go to some lights we don't have extras of:
BTN 750W 120V
FEL Q 1000W 120V
BTL 500W 120V
GLC 575W 115V
EGG 750W 120V

I have some time tonight to see what I can find to match the extra lamps.
 
Those old frensels with the really old incandescent lamps will use halogen BTL's without any problem. The incandescent lamps for the medium prefocus base are very obsolete. You'll gain light output, lamp life, color temperature, and reduced cost by upgrading to halogen BTL's. Your BTN's will fit, but don't use them since the fixture isn't rated for 750w.
Your PAR cans will accept any PAR64 lamp of the four beam angles, wide flood (WFL), medium flood (MFL), narrow spot (NSP), or very narrow spot (VNSP). They haven't changed very much over the years, so anything you get nowadays will work.
The EGG lamp is generally used in old radial ellipsoidal reflector spotlights like the Altman 360 (first picture). Some scoops also use the EGG as an incandescent replacement.
The GLC and FEL lamps are used in newer axial ellipsoidal reflector spotlights like the Altman 360Q (second picture). The GLC is the much newer, higher efficiency lamp. The FEL is somewhat obsolete and inefficient.
 

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As long as we are way off topic and waiting for our buddy to check back in with pictures for us to identify...
I keep a couple boxes of those little medical alcohol pads around... like they use to wipe your arm before the shot. You can buy a box of 100 for like $2. Every time I open an instrument for any reason, the last thing I do is wipe the lamp off with a swab just in case. It seems like a good thing to do and I'm amazed at how much dirt comes off lamps. I even open them up once a year and give them a wipe down. It seems to have a positive effect. But I don't have that much inventory to really have a good sample size to see if it's working. Curious what some of you guys who deal with a lot of gear think of the idea.

Normally the medical wipes are Isopropyl Alcohol instead of Denatured Alcohol. It's not optimum but in specificacally asking about this, those at Osram I asked said it was suitible as a substitute that works well enough to clean the lamp. Yep it's a good solution. I have a McMaster Carr part number for like 8"x8" Isopropyl Alcohol wipes if anyone is interested.
 
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!!! logging in/out problems... just lost like 3 hours of attempted message or refinement on it.

here is the last section of the post at least.... Computers suck!.

On the Fresnel, if you found it’s name plate voltage/lamp ratings, it should have also had a brand name and part number on the fixture. Expect this might be a yellow sticker like thing on the lower side or rear of the fixture? Such info would be required on any such sticker plate as per your toaster oven also having such a plate/sticker on it. Given the info so far, it makes your Fresnel date from at least the 1960's to about at most 1978 I would assume. Likely there will be more than one brand of Fresnel and era in the inventory also. That you also didn’t instantly see anything like “Century” stamped into the fixture or handle/knobs also helps to limit what specific fixture you are seeing.

Concern of original asbestos wiring, how it’s wired even if not, grounding, condition of wiring and lamp base and many other details given the above details and lamp used become concerning - get these fixtures inspected by a professional in the industry. Do a “search” and studying into past posts on the word “asbestos” and while you should not get panicked, you should be concerned in a educating yourself and follow up type of way on something that strikes a note as possibly in real need of attention due to what you say so far.

On the PAR, measure the gel frame size and or the opening and that would be sufficient to know what it is. 1Kw/120v however says PAR 64 - no such thing as a PAR lamp in this wattage of a different size. You want to find and educate yourself about the four various beam spreads of this lamp. Time to get a book on stage lighting so as to teach what you learn further, or at least know what gear you are working with so as to design with it better. A search into “book” will lead to lots of books to look for.

The PAR 64 lamp in having an inner halogen capsule part of the lamp and outer globe of soft lime glass also is safe to touch. Given these two lamps you mention, it makes it curious your original observation as to what caused the bubble? Different lamp?

No need for gloves in either above lamp, but if you do implement a glove policy for other than gloves that can take some heat should you have to focus or in the case of the PAR 64, have to “spin the bottle”, make sure that your gloves are of specified types. IN handling halogen lamps, first they must be “powder free,” “smooth” gloves of PVC, Nitrate, polyetheylene or latex. Latex gloves are the most common in use, avoid them if you have young ladies potentially on the crew - latex in general, including with paint has a cumulative effect on the reproductive tract that is not beneficial. Beyond that, there is proper sizing and more important yet concepts in wearing the gloves.

Have to properly train your crew that the gloves are only there for changing the lamp and not reusable unless they only touch lamps or reversable. You will often find people holding onto a ladder with the lamp changing glove, holding a screw driver, focusing etc. with such a quartz glass holding glove. Dirt from any other surface than the lamp can be just as bad as touching the lamp with one’s oily skin. Kind of fun, if you catch a lamp early enough, you will actually see the finger prints in white now etched into the glass of the halogen lamp. This might also be from touching the lamp with fairly dry skin but skin with just enough oil so as to etch the finger print into the glass.

BTN - is a 6" Fresnel lamp as similar to your DNW lamp. Don’t use it in your 500w rated fixtures for now until they are upgraded.

FEL - is a Altman 1000Q follow spot lamp. It’s possible it was bought for other say Leko / ERS fixtures but don’t use it in them unless rated for that lamp by way of name plate/rating plate you saw on the Fresnel. It’s a crap inefficient lamp.... urr, do a “search” into those despised “FEL” letters and you could read more.

BTL - now there is the DNW upgrade lamp - again the DNW is just fine for a lamp, use them up than only buy the BTL’s.

GLC - you must have some form of Altman 360Q axial Lekos or axial Lekos of a similar type. That’s a good lamp - smaller filament that’s more effiecient but a lamp that is not very cost effective for lamp life. You would be better off with a GLA lamp as similar to it but the long life version. This if not a HPR lamp as similar to GLC in having a less efficient filament for gobo projection but a internal reflector (sound like a broken record) for 15 to 20% more output. The GLA lamp is not a bad lamp, it’s just not the primary choice for overall output or cost effective long life. Save if possible these GLC lamps for pattern/gobo projections, than shoot for the more economical GLA lamps.

EGG - Had to look it up to verify, yep you have some radial Lekos also. It’s a similar to the DNW/BTL lamp for the Fresnels but longer in “LCL” (Lamp Center Length). Focus fins to center of the filament. This is a halogen replacement lamp for the Lekos as if DNW/BTL lamp a “DNT” incandescent lamp that will have originally have been used in your radial Leko fixtures. Such lamps due to smaller optics available by way of hole cut in the reflector to fit the lamp in, the lamps for the ellipsoidal reflector spotlight / Leko / ERS in being a spotlight instead of Fresnel or PC with wide body and lamp in front of the parabolic reflector was more long than wide thus the extended length in still providing sufficient cooling area for the filament but only with a longer lamp instead of wider more squat one.

Given this lamp in stock which has the same lamp base as what’s used on the Fresnel, you will tend to want to inspect your inventory. It’s frequent that you will find a say BTN lamp shoved into a radial Leko and that Leko gets light out just not very efficiently, and difficult but at times possible to install the EGG into the Fresnel fixture with also a not efficient beam of light but at times enough light coming out to fool you. Such lamps given the same lamp base will often wrongly be installed into another fixture.

The EGG lamp to date has no better improvement. Should you want more output/shorter life you go with a EGF, otherwise due to the size of the hole in the reflector, such fixtures if optimized can be useful for supplemental and especially the amber colorings on your stage. Your GLC based fixtures no doubt are bright blue in comparison to these almost yellow ones.

Note in my terms “radial” verses “axialleko. I assume you know what a Leko is, the Radial Leko has the lamp housing off at like a 45 degree angle to the center axis of the lamp. The axial fixture than is obvious but a good test question for students should you get a stagecraft class.

Otherwise on what will have been a further comment, make sure that what you learn and find in study you share with your partner and right arm at the school. Have to keep both of you on the same page by way of vision, tech and concept or you will both quickly go into different paths. Discuss, debate, provide a copy of what you study to the other person so you stay in the same place given a similar goal and noble effort. Ever so important that you two become a team.
 
Ok, let me attempt to re-create what I posted in “quick reply” but found lost in “you need to log in first”....

The old Fresnels are using DNW lamps or at least that’s the spare lamp you found for them. Check your lamp and fixture again. Should more likely read something like 120VAC-5A as VxA=W reveals that if the fixture were rated for 15A, it would be able to take a 1,800w lamp.

The DNW is fine to use, a bit lower in output but fine to continue using. Tag such fixtures using this lamp and use them especially for your amber washes. Save two or three lamps for educational purposes. This being one you personally buy at the cost of a BTL lamp and put away for later days, and two for class - should you ever get a say stagecraft class to teach. This lamp especially if it works will be very useful in teaching and even demonstrating the “halogen effect” in all ways including color temperature, output and bulb size.

Also note on your DNW lamp, Under the wattage and type will also be a note of Base down to horizontal. This is very important. Hang the lamp in another than 180̊ to down direction and it’s filament hangers won’t so well support the filament thus causing possible a failure of the lamp.

DNW G.E. #21887 (Disc.) 64/CL, Incd. (HRG); 500w/120v; T-20 (globe diamater measured in 1/8" increments); c-13 (filament type and supports); LCL 2.3/16" (measured from the alignment fins to the center of the filament); P-28s (medium pre-focus) lamp base; Base Down to Horz; 2,900̊K in color temperature; 10,000 Lumens; 500 hours of life.

Note that you can touch this lamp. It's not using a quartz glass, instead it is using a soft lime glass as similiar to your normal A-19 table lamp lamp. This or as per the "HRG note" it's using a heat resistant glass that's a form of soft lime but a little more heat resitant - still able to be touched.

The better lamp of course is the BTL for this fixture:
BTL G.E. #11966 (T-17 Euro/Lif code) CL, Quartz; 500w/120v; T-6; c-13; LCL 2.3/16"; P-28s; (Base Down to Horz - often upgraded including this lamp to universal burn in later versions); 2,950̊K; 11,000 Lum; 750hr

Same basic lamp, better life and output due to the "halogen effect." It's possible that your DNW is from Wiko/Eiko. This company might still be making the DNW but it's not as cost effective of a lamp.

Also in your inventory might be the "DLC" or 250T20/47. It was very common in the days before lots of dimmer channels and in fighting amber shift that a lower wattage lamp would be installed in a fixture where full output was not necessary. Gonna have to inspect your inventory for such lamps and yank them for other than special service should you find them. Otherwise they will become a black hole in your light plot. Good lamps, also long gone but not something you want to be un-aware of.

250T20/47 G.E. #20762 (disc.) CL, Incd. (HRG) 250 w T-20 c-13 LCL 2.3/16" P-28s (Heat Res. Glass, Base Down) 2,900̊K 4,600 Lum 200hr
 
Ok, like chapter three to my lost post.

The PAR 64 lamps as described - there is no other 1Kw lamps available in other sizes (again measured in 1/8" increments) are made of soft lime glass on the outer globe and halogen glass on the inner capsule. Perfectly safe to handle the outer globe. Wondering what the lamp was that was touched in making the bubble - no doubt the FEL. So both your DNW and your say FFN are safe. It’s possible that your PAR 64 lamps amongst four sizes are not an ANSI lamp which is perfectly fine to see. ANSI PAR 64 lamps are FFN for 1Kw/120v Very Narrow spot, FFP for Narrow Spot, FFR for Medium Flood and FFS for Wide Flood. As said, your PAR 64 lamps might not be ANSI lamps rated for 120v. It’s often very economical and wise to switch to a 130v version of these lamps in getting a longer lamp life.

This given you need a 1Kw instead of 500w/120v if not 500w/130v version of the lamp. Another thing to check for is what wattage all PAR lamps are. As with fighting “amber shift” above with the 250w Fresnel lamps, and as per amount of dimmers available, at times a 500w if not long discontinued also 600w PAR 64 lamp amongst other 800w or 1.2Kw lamps might be in use in a you gotta get a handle on both inventory and lamp used type of way.

Believe last note I remember was about further refining “getting a professional” out to visit your situation in helping you evaluate. You need an evaluation as to what you have both due to the suspected wiring, and to find out condition and to help you and your right hand person come up with a punch list of what to fix now, what to upgrade and what to service. This person also can otherwise either do much of the fixture repair work or supervise the work done as opposed to sending the gear out to be done for you. Either way, you need someone that has further training in such things. Contact your local IA branch, your local and especially state college or professional theater in getting a TD or ME rated tech person to at very least pay you a visit and offer and assessment and advice. Your local college will if you are a school have some form of responsibility for you and your theater as a sub school under them , play on this. Get a relationship going also. In time, you borrow or rent from them, they rent or borrow from you. This much less TD to TD, you all work together and or might get stuff from their higher budget. Same concept with a professional theater of the area IATSE if no college is closest. Someone with much more professional training is going to be responsible to help you take control of your theater - this even if the local theater supply place that will to some extent at least do some amount of advice for free. Tech person to tech person you might have to pay for some help but responsibility is there somewhere - have to find who is responsible for you most locally and will at least be on speed dial for you.

That’s a start hopefully and of help. Remember to have fun. Years from now what even was not fun at this point will hopefully be legend enough that it will become a form of really living it or living the life of.
 
And there is your Ship text book on lamp replacement.

Many lamps come in some sort of plastic bag or foam padding. If you are careful... and not up on a ladder holding on for dear life... you can often change the lamp without touching it by simply using the packaging. Again I wipe it down afterward with an alcohol pad but as long as you don't touch it that isn't really necessary.

A couple of book suggestions.
1) "Amazon carries the 3rd, 4th, and the brand new 5th edition. The basic lighting theory is the same in all three books, its mostly just the new equipment information that expands between editions. So if your goal is just to better use your old system the 3rd edition will do just fine. The new 5th edition is like $65 but you can get a used 3rd edition for around $10.
 
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