Thorn 600X lamp


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Good question, probably best placed in lighting questions not general question of the day type challenges most should be attempting to answer in testing their general tech knowledge.

Below is to the best of my knowledge on this lamp - I could be wrong but no so by much especially in things I have questioned the various manufacturers about. (This series of lamp being a sort of pet project of mine in the industry.)

The Thorn HX-600x as a specific lamp - given that's what is stamped on the description code along with Thorn as the actual lamp, is not cited in my notes as a Thorn lamp. (Possible it exists and is not in my notes but doubtful.) I'm not aware of any Thorn lamp since about 1992 in the HX line other than dogmatically following the Alternate temporary ANSI lamp designation which does not include "X's" to the best of my knowledge following the numbers - they are only used in the prefix as it were. Nor am I aware of duplicate numbers for both high output and long life lamps ever used since than. I do have some PAR 64 HX-156 lamps that are both WFL and NSP, but they are old and became the ANSI GFB and GFE later. The HX/HP series lamps are for more than just Leko type lamps.

The Thorn HX series these days will be always be much similar to that of a ANSI coded lamp - one very specific lamp only with a new HX designation such as HX-601 for the long life version of the HX-600. The HX-601 from Thorn is definately a Long Life Thorn lamp just as Thorn is still I believe making HX-600 non-FLK lamps. Thorn at times will do the ANSI lamp, at other times will leave them as HX series. This is also totally indipendant of what GE is doing by way of adopting Thorn experimental lamps and or classing even lamps with the same part number as ANSI lamps such as the FLK while Thorn at least for a time or is still calling it the HX-600.

There is also is no such thing, officially by way of ANSI codes at least, a long life FLK-LL lamp or any ANSI coded HX-601 lamp - it's a crappy lamp replaced by the more efficient HX-605/GLA below. Such lamps posing as a ANSI coded lamps are not following any ANSI system thus are indipendant of the standards involved with classing such a lamp.

The GLA lamp replacing the HX-601 has a more rugged filament and better efficiency in all ways. No reason to be buying HX-601 lamps other than if it's more cost effective than a GLA and you can deal with less output and a 8mm wider thus larger filament that won't do patterns or even output the light as well. A FLK/HX-600 and in theory the HX-601 has a 8x18mm filament. The GLA/HX-605 has a 8x10mm filament. This in addition to much more output and often better color temperature and even lamp life. GLA lamps are very dependant upon brand in these classes - each brand and even dependant upon what catalog you look at from any brand will have changing data but all are better than that of the HX-601 in one way or another.

Also after approximately 1992, the Thorn HX system uses all even numbers to designate the high output lamps, and odd numbers for the long life versions. There would be no reason for Thorn to designate a lamp as HX-600x in meaning it as a long life lamp - they already have the HX-601 designated as this. It's possible but not probable that if Thorn is making a HX-600x, that its' a upgraded High Output HX-600/FLK lamp instead.

Osram in not as dogmatically following the HX / HP system very well did or does have a long life HP 600X lamp #54516. This specific lamp is discontinued however. It became redesignated as a GLA Ansi Coded lamp along with the now redesignated to be GLA, GE/Thorn HX-605 (though I believe the HX-605 innitially was the 230v version of this lamp. At this point the HX-605 by Thorn is very specifically a GLA lamp, and this along with the HX-604/GLC is the better series of lamp to be using, see above.) HP is normally much like HX in designation, normally by "in theory policy" at least, HP designates a different filament such as that of a HPL in otherwise being a HX-600 but with different filament. "HP = Paralled Coils to the filament. HX = coiled coil flament." This official description is sort of innaccurate given very different filaments between that of a HPR and HPL lamp, but still the only difference I'm aware of in designation. Normally it's just that GE/Thorn does HX, Osram does HP and Ushio chooses what ever they want with Phillips not using that system at all.

In other words, a HX-600x coming from Thorn I find doubtful as a actual lamp. While Thorn is still kept alive by GE in a not so well alive way, and often acts as sort of their un-advertised R&D department for the Stage and Studio line, there is no info on the company other than thru the exclusive to the US supplier of them L.E.Nelson Lamps / PRG. (Yep, PRG did buy them out but it's not a 100% buy out by way of this Thorn connection.) Gonna be meeting with someone from GE in the Stage and Studio research and development section in the coming weeks, I'll harp on GE/Thorn info and why they don't publish useful info more in the coming weeks. Should be interesting. Otherwise L.E. Nelson lamps is still the only supplier of this lamp in the US. Everyone else buys from them. Doesn't mean one shouldn't buy from who ever is supplying this lamp to you - there is dealer/volume discount factors, it just means they are all coming by way of this only supplier (which might change in the coming years dependant upon what PRG is doing with their now exclusive Thorn contract as it were...)

End result, it's possible that you have a Thorn HX-600x lamp. Given that's the case, I would suspect that it's an upgraded HX-600/FLK lamp and not a long life HX-601 as it would otherwise be. Possible that Thorn copied Osram's internal refleflector technology used in the HPR 575/115v lamp. If that's the case, you now have basically a HP-600 lamp (HX-600/FLK) with a internal reflector that completes the ellipsoidal shape of the reflector. In other words, you now have a lamp that's 15 to 20% brighter than a FLK/HX-600. Otherwise less likely perhaps Thorn has come up with a better pinch seal in copying GE's (what is it the "Shark") they designate with x - though I would expect that Thorn would just make the upgrade and not change the designation for this little detail. Could also be that the HX-600x is some more advanced technology such as say a liquid cooled lamp - but highly doubtful about this and or that they would keep the same HX-600 number. Perhaps "x" designates a dichroic coating to the quartz globe of the lamp. This would be something that the industry is also working on for this type of lamp but to the best of my knowledge is yet to come to the HX-600 lamp or even HPL lamp. It is the case with a DYS lamp and a few other halogen lamps, just not tubular shaped lamps yet.

In any case, the HX-601 lamp if that's what it is, or other brand of say FLK-LL or odd brand calling their long life lamp a HX-600x, than it's a crappy lamp.

The best lamps for these fixtures are as follows without substitutes that I'm aware of at this point:
GLA/HX-605 - Phillips, GE/Thorn/Osram and Ushio all make this lamp. I prefer the Phillips #6992P in still having the best specs to the lamp but all make a dependable product that is more efficient than any HX-601. GE/Thorn and Ushio both make a HX-601 lamp. Wiko/Eiko might also though I don't have notes on one yet.

For high output, the GLC/HX-604/HP-600 lamp by GE/Thorn, Osram, and Phillips in their alternate to the HX system #6989P lamp is the lamp that will have the most compact thus efficient filament. As with the GLA lamp above, it features a more rugged filament and improved output. I don't have an opinion on this lamp amongst suppliers. Phillips might or might not have a longer life version of this lamp but it's very dependant upon what catalog you are looking at. I have six different listings of this lamp from them and two different lamp lifes listed. One is 400hr, the other 300hr as normal to all brands.

For other than pattern projection, or perhaps very refined optics such as installing it in a 360Q series of fixture, the Osram HPR 575/115v lamp is a better lamp to install in a 360Q or 3.5Q fixture of any brand in 1980's style fixture. The internal reflector (above) completes the ellipse to the reflector and makes it at very least as efficient as a more modern say Shakesphere or even out output a S-4 fixture of the same beam spread when one compares one fixture's beam to another. As said before by me in testing, you could see the beam of a 3.5Q5 inside a 50 degree S-4 Leko's beam of light. Not just see it, but clearly see the edge of the 3.5Q5 edge of the beam. This lamp cleans up the "Altman dark spot" associated with the hole in the reflector making for the blackspot at the center of the beam angle, and in many ways makes the 360Q fixture become just as efficient or at least for the most part as efficient as that of at least a Shakesphere fixture. This perhaps other than for pattern projection. It's also a lot easier to bench focus fixtures with this lamp - normally as long as close to bench focus, you cannot optimize it by much - very flat field to the beam with a very hard edge even in a 30 year old fixture.

If you have the budget to do high output lamps, I highly recommend the Osram #54549 HPR 575/115v lamps. Filament size is 6.35x11.68mm cc-8 as opposed to that of a GLC with a filament of about 9x7.5 or 9x8mm c-13D that's smaller and more square but not by much really more efficient. The GLC is normally 3,200̊K; 15,500 Lumens in output and 300 hours in lamp life. The HPR is the same color temperature 3,200̊K; 16,500 Lumens in output + the 15 to 20% efficiency boost from the internal reflector, and 300 hours in lamp life (both in lamp life at 115v not 120v.)

If reading enough to this point to get your answer, you might assume that yes the HX-600x lamp will work in a 360Q base fixture. IT won't work in the medium prefocus (P-28s) based "radial" type 360 line of fixture but will in the Medium Bi-Pin (G-9.5) based "Axial" type 360 Q (for "Quartz"/halogen) fixture along with just about any other Leko using a G-9.5 based lamp.

Better than the HX-600x lamp would be the above lamps of course.

Reasons for it working is that while Altman has not to the best of my knowledge in the fixture specs changed the UL listed lamp options for the fixture to that of the HX-600/GLA type lamps, they as a company do cite these types of lamps as suitable for their fixtures. They recommend the upgraded lamp bases and reflector kits however due to the extra heat. But given such fixtures are rated for [email protected] and you are now installing a [email protected] lamp, it's electrically and for the most part heat wise safe to use. In discussions with them about it, use up your old reflectors and lamp bases, they shouldn't really suffer much due to the extra heat - mostly when they fail and they will eventually, it's more due to the normal mortality of such reflectors and lamp bases due to the heat. Upgrade to the Altman #97-1580 lamp base and or something from Buhl, Osram, Bender and or Wirth for high temperature TP-220 lamp base all recognized by Altman as suitable. The Production Advantage featured Ushio brand of C-3A lamp base while very similar to all above lamp bases and has proven to work well is not UL listed for the Altman fixture. Works and there are no known problems in it's use, not UL listed for use in this fixture - your choice.

On reflectors, eventually the old reflectors will get old and need replacing. If say a late 1990's reflector or of odd lot number, the T-6 lamp normally associated with a HX-600 type lamp might be a really close fit within the reflector. Unless you have at least 1/16" between lamp and reflector (you need to look at the lamp after bench focusing), you are probably best off replacing the reflector. Any lamp that touches the reflector won't last very long. This is a in general safety and lamp life tip for all bench focus procedures no matter what lamp you are using. Once the lamp is bench focused, open up the fixture and look at where the lamp is in the reflector. Might even pre-center the lamp on the reflector before the bench focus than follow up with an inspection afterwards.

Still, that closeness with some lot numbers of 360Q reflectors to the lamp has been the only problem I have found so far. For the most part it's with the 3.5Q5 fixture on the other hand which was never designed to house a T-6 lamp but does work fine with one. Major note is to look at the fit about the hole in the reflector as compared to your lamp in operating position. This could also be very important in general beyond any lamp with using a EHG lamp also which often tends to be T-6 in size but at one point was T-5 thus the smaller reflector holes.

Lamp bases especially if the old #58-0017 socket will suffer from heat problems in general normal to the base no matter if HX-600 or EHG in the fixture. This will exhibit itself by way of silicone insulation melting away from the SF-2 wire leads as they leave the lamp base, or charred contacts thus pins on the lamp base also. When ever you remove a bad lamp from a fixture, have a look at it's two pins and see if you see arching, blackening, pitting and other signs of damage to it. This would tend to mean also a bad fixture lamp base that needs replacement.

As long as these two things are the rule - in addition to just looking at the reflector not only for how centered the lamp is within it but it's overall condition - no fogging over or white spots or small bubbles forming, and if policy now say three things each time you change a lamp and it's perfectly fine to use old lamp bases and reflectors with new lamps. Or in general even use old stuff with new lamps of the same type. A little more observation and preventitive maintinence is all that's needed.

Heck, while the fixture is cracked open with each install, have a look at the shutters in having a look for any problems with them. Sorry, no improved shutters or even dichroic reflectors available, still keeping an eye on the fixture is not a bad thing.

The theorized HX-600x lamp is 100% useable with the 360Q line of fixture.


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Thank you ship,
Just some extra notes on these Altman fixtures, they are the brown paint color axial 360Q-6x16, They appear to have newer faceted reflectors (1997 to 1999 faceted reflector; pre-super reflector), but to my knowledge the reflectors aren't of the super reflector series. I am also 100% sure that the reflectors in our older brown paint color 360Qs are not the older stamped aluminum reflectors.
Secondly: All of the brown 360Q units our school owns have just been replaced with source 4 fixtures and the 360Qs are now extra fixtures. They all seem to have blue lenses (except for 1 unit) and reflectors that are in good shape. The units are also the ones that have a factory installed iris and I would like to know if it is possible to remove them since almost all of the irises that are in the units are also pretty burned up and warped. The only problem is all of the units have shutters that are severely warped and burned up. Since our school is short on money and our technical director thinks the fixtures won't be put to use too much, what is the best solution to replacing the shutter blades?

Another Question: First of all, how many different reflector models are there for the Altman 360Q (axial Quartz Ellipsoidal)? And, where do I find the reflector's lot number and what year would that lot number correspond to?(basically could you list some of the 360Q(axial) reflector lot numbers and their corresponding year of release)?


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Mmm, blue lenses and reflector lingo... someone that knows his fixtures. Well done, caution about the lamp bases but still, use until they wear out.

Pop the HPR lamps into them and they will compete with the S-4 for usefulness. Doesn’t matter the color of the paint, only thing that comes up now is lot number to lot number changes common with both colors of paint. Standardized parts works up until you have to swap out lens trains etc.

(Use the green lens unit for applications where the gel is amber and it will be fine. This or one can always use a spare parts fixture.)

Iris’s are fully removable without any problems what so ever. Also they are 100% replaceable with modern ones for the fixture from any number of companies - the iris is the same as for instance would be used on some follow spots etc. You can also take them apart - carefully and make good ones out of the still good if any leafs. Crocus cloth, various fine grade silicone based grinder wheels, spray graphite and you can perhaps save a few. Trick is in re-assembling the iris. (A note, a 6" Leko Iris is as a concept able to fit into a 3.1/2" Leko and work well - got or at least used to own one that someone before me installed one into.) Probably won’t need the iris’s given the drop in ones for the S-4 and better optics. Save the good spare parts for your follow spots or if needed later. If memory serves, the it's also the exact same iris used in a drop in Iris to a S-4 fixture. Get a few blades with a kink in them, you now have spare parts - all be it a pain in the rear to replace.

Shutters are really easy to replace, drill out the shutter handle/fiber washer (hold the thing with Vise Grips while drilling,) and grind away or drill away the rivet. Once done, remove the gate from the fixture and slide out the shutters. Easy project. Slip the new ones in (wipe away some of the oil coating on the new ones), re-install the gate (use a Sharpee to do a whitness mark on it and the fixture as to it’s alignment), and rivet the new often fiber/plastic handles onto the shutter. Use 5/32" aluminum with aluminum shank rivets of about 5/16" and less grip range on them unless of the 1/8" style which requires a smaller aluminum rivet. Use of steel rivets makes for too much tension on the fiber or plastic handles and tends to tear them up. This also assumes a double fiber washer on each shutter - otherwise a 3/16" grip range rivet would be suitable.

The shutter has had no major improvement since the 1960's. Graphite up old ones that are not deflected and burned, or anvil pound flat and fiber grinder wheel if not even soft coth wheel out your somewhat good shutters. Most important part of a shutter is the blade edge. If it’s not so good, it’s possible to grind a new edge on it as long as once you are done it’s perfectly flat and has no abrasive edge to it which will rip up with the heat. On an average shutter, you can probably loose 1/4" of shutter edge before you start to loose the ability to control the light with it. But it’s only useful for shutters that are not hugely bad. Should you use a steel with a sort of grain to it, have that grain run parallel to the blade edge.

If really careful in saving money, you can save the fiber washer handles and re-use them as long as you use rivet washers for most of them which gain expanded holes. That will save some cash.

Otherwise while not very expensive, try having someone make shutters for you in copying one. At one point early on I cut some aluminum Colortran Mini-Ellipse shutters out of 5/64" aluminum plate. Wasn’t perfect, but they lasted a sufficient amount of time. Better would be stainless steel for a shutter. Overall, a shutter is not in an absolute sense very difficult to make even out of steel flashing. Primary concern is that blade edge having a perfectly flat and smooth surface. In laying out a shutter, perhaps lay them out so the edge is the factory edge of the flashing and you are in good shape.

For a tempory and cost effective fix, why not look into making some of your own. Somewhere between say 16ga steel shelf dividers to a steel shelving unit - popular way back and often tossed in the trash these days which are now scrap steel, any flat steel you find, aluminum or steel flashing, heat duct work, a pie tin, and in general stainless steel plate (difficult to cut and drill but the best), you can at very least come up with some metal that in one degree or another should take the heat for at least some amount of shows before you have to replace them. Heck, make extras. Key is that flat blade ege and you can for the most part fudge up to 1/16" thick or 16ga steel material making up the shutters.

Have a look at your gate plates and divider plates while replacing them. Buff them shiny again and lay on a heavy coating of spray graphite (whipe off the extra after it sets up.)

As for lot numbers and stamps on them of the reflectors. There just is lot numbers and differences but nothing marked. Compare a T-6 (3/4" dia) lamp into a number of reflectors old and new and you will detect two sizes of hole. Most new reflectors should already be sufficient for a T-6 lamp. Heck, installing new reflectors into the fixture should be enough to tell you that the mounting holes most often are of some thus there is differences. Not a big deal.

Overall, hole size is not much to be worried about, just something to be aware of especially in verifying your bench focus. Same part number from Altman means no lot number/part number changes means no way to track what might or might not work as well. Relax, as long as your bench focus is good, even the reflectors with the smaller holes in them should work fine with newer lamps.
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Should The older yokes be replaced (most have stripped bolts and worn clutch plates (old style serrated))? Also how often should 360Qs get cleaning and bench focusing? I am asking this because from the day these units were once new, up to now (25 ish years) these fixtures have never had and bench focusing done, no lens or reflector cleaning, and no standard maintainence up to now. This is because have the people in my school's "tech club" (we run the lights and sound for shows) do not know what they are doing and think that if it lights up it doesn't need cleaning or maintainence. Also, is a faceted reflector in a 360Q most likely to be a super reflector or the model before the super reflector. This question came to my mind over last summer when I worked in another theater where there are newer (1999-2000) 360Qs that have blue lenses and what looks to be superreflectors. To my knowledge, there are two different faceted reflector models, the first is the one that was sold to replace the stamped aluminum and the second was the super reflector upgrade kit. Can you verify if that is correct?


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Whoops!! didn't finish my post there, any way, for an altman 65Q fresnel, what is the best lamp to use? currently we use really puny BTLs. Also, for Source fours, what is the best lamp out there, is it Ushio? Currently all of our ETC fixtures use the Osram-Sylvania HPL 575/120X. The only Ushio's in our inventory are the ones that came with the new fixtures that we recently got. (some 26 deg Jr., 19 deg, PAR MCMs, and 10 Degree fixtures)


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HPL 575LL (120v) G.E. #37816 (?disc.) (?Disc.) CL, Quartz L. Life, S. Coil Sq. Filmt. 575w/120v T-18mm 10.5x6.9 LCL 60.3mm G9.5*HS Any Burn Pos. 3,050̊K 12,360 Lum 2,000hr
HPL575/LL/C (120v) G.E. #92435 CL, Quartz Long Life (HRG) 575w/120v T-6 10.5x6.9 LCL 60.2mm G9.5*HS Universal Burn 3,050̊K 12,360 Lum 2,000hr
HPL 575/LL/C/120V GE #92435 (11/05) CL, Quartz 575w/120v 4-C8 G9.5*HS “Six Sigma Process” 3,050̊K 12,360 Lum 2,000hr
HPL575/120/X Osram #54815 CL, Quartz Long Life, Ultra Plus (UCF) 575w/120v T-6 4-C8 LCL 60.3mm G9.5*HS (Ultra Plus) Any Burn Pos. 3,050̊K 12,360 Lum 2,000hr
HPL-575/120X+ Ushio #1002283 (JS120v-575wX) CL, Quartz, Low Seal Temp. 575w/120v T-18.35mm 4-C8 LCL 60.3mm G9.5*HS 3,050̊K 12,360 Lum 2,000hr

Yokes are just steel, if you wish to replace them, they should be able to retrofit to the newer style of clutch break with some work. Overall, I wouldn’t change them unless the confounded cast aluminum clutch breaks are no longer available. That’s more an issue with training your tech people to loosen handles before moving the fixture which will also screw up a clutch break, than with a necessity to upgrade.

Confound as you will other generations of tech people, decent fixture that last between generations is why it is still serviceable. Unless the clutch plate has it’s wings broken off which hold them in place, I’m not aware of wear issues with them and they should be fine up to say 6x16 and if double clutch plate lock, fine even than.

Again, not aware of markings and or other than “gee this is different” by way of various lot types and models of reflector in Altman gear. Stuff changes, best I deal with.

Bench focus/cleaning - depends upon your situation. Are the carpenters in there while lights are on stage and hung, is it a heavy fog/haze show? Is dust the largest issue? Once a year at least, some times every time they are used. Do you strike your fixtures after every show? It’s a rugged fixture - both fixtures in question, could be just fine in every other or once in a while as they need work. Could also be possible with just going to a sticker on the yoke citing the date and who did the last bench focus so various or individual fixtures can be pulled out of line as you go when it’s time. Were it not for “various generations” of lighting technitions, those of a new generation could be offered up as much opportunities to learn on their own as opposed from the program where they have to wait. Ask any teacher on the forum about “generations” of students and they will no doubt confirm that it all runs in cycles - yours perhaps good, or you being a star of the program, and a future class will again go to sleep. A generation after you will have students such as you (assuming a student - no offense) that will pick the program up again. Light fixtures if designed well can often withstand a few years of sleep by way of their care.

On reflectors, there is the concentric ellipse shape without any interruption between them, the concentric ones with two or three sectioned off areas of it’s focus, than the honeycomb types. Which are which after that in lot number and what has what size hole - all perhaps will have this problem as a separate issue or thing to note. “Super Reflector”, for me that’s a term only.

On a 65Q Fresnel, there has been no real changes to the lamps since the 1970's. The BTN lamp is the best 750w lamp, the BTL is the best 500w lamp. I don’t expect any upgrades to this type of lamp to come in the coming years. It’s kind of a dead in lamp style that has enough activity that it will be manufactured still but not enough activity that it will ever see more than perhaps some form of “Blue Pinch” type pinch seal technology. Don’t expect a 115v version of this lamp for instance.

On a S-4 fixture, what’s the best lamp out there? Don’t know. Just bought a few hundred GE versions of the lamp as opposed to my past buying Ushio and Osram and a few Phillips also at times. Don’t like the box of the GE lamp as much so far. Yes, I mean the box the lamp comes shipped in. For me it’s often a disqualifying factor the box a lamp comes in. I for instance won’t buy any GE or Phillips CYC lamps simply because the box the lamp comes in sucks when it comes to that lamp having to survive a world tour as a box for the lamp in it being a spare lamp. The Ushio and Osram boxes for this lamp are better on a CYX. On an HPL lamp, Ushio lamps survive but have that tab that comes undone or breaks. Osram HPL lamps have crappy cardboard but small size and foam between the lamp and damage. Phillips HPL lamps don’t have foam and last ok but not great as a lamp traveling around in the back of a truck. The GE lamps... don’t know yet.

Ah’ you were meaning “best lamp” not best packaging for the lamp... When I became the lamp buyer, where I work in having started with Osram lamps went to Ushio lamps in now only buying Ushio lamps for their S-4 fixtures - much more output and they had better output and reliability. Lamps changed and reliability changed. To be honest, these days I cannot tell the difference between any of the main four brands of lamp and even if slight, would not care for our purposes in a moving light based “entertainment lighting company.” Bought the GE lamps for $2.00 per lamp cheaper than the Osram or Ushio lamps I normally buy. After that, I cannot tell the difference. All lamps went thru major upgrades in the last four or five years and all to the best of my knowledge are the same now in both reliability and output. Only remaining difference is in ceramic base verses aluminum heat sink base to the lamp. I’m a fan of aluminum, but there is specific “as advertised” benefits to ceramic - especially the improved ceramic bases especially in an out door fixture from what I remember.

My advice for the most part - don’t matter on a HPL lamp. At times say for a very specific 120v/750w Long Life lamp, perhaps the Ushio will blow out where the GE doesn’t sooner - but such an observation takes both time and very specific application to prove. Go by lamp price until you can prove such details.

You have the 575w/120vX lamps. That’s a crappy lamp. About as bright overall as a 115v/375w high output lamp in reality. Ushio to Osram... in this dim lamp... shouldn’t matter.


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I tried to get my club's adviser to buy HPL 575/115v or x but he wants the long life lamps since we got through a lot of them and he doesn't want to deal with ordering lamps every month.
Our school orders lamps only about 3 times a year, at the beginning of the year, before Christmas break, and then some time in May.
I believe that the HPLs that are in our new fixtures at this point are Ushio 575/115v. We about 20 Source 4 PAR MCMs that are lamped with Osram 575/120X lamps and used as house lights. Now the fact that they are house lights is beyond my knowledge and makes absolutely no sense to me.


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I tried to get my club's adviser to buy HPL 575/115v or x but he wants the long life lamps since we got through a lot of them and he doesn't want to deal with ordering lamps every month.
Our school orders lamps only about 3 times a year, at the beginning of the year, before Christmas break, and then some time in May.
I believe that the HPLs that are in our new fixtures at this point are Ushio 575/115v. We about 20 Source 4 PAR MCMs that are lamped with Osram 575/120X lamps and used as house lights. Now the fact that they are house lights is beyond my knowledge and makes absolutely no sense to me.

I think S4 Pars make great house lights, but I think I would have gone with the cheaper model if that's all thier doing. 'Course there are also a lot of other PAR lamp choices out there to use as house light as well.


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Depending on the height I'd use WFL with a warmer gel and maybe a frost to soften it up a bit. If they're really high in the air, I'd use a MFL to keep the light from spilling too much on the wall. Be sure the lenses are rotated correctly (and be consistent), because the faceted lenses (MFL, WFL) don't have a circular beam. House lights should give a very even wash of light in all parts of the house, so place them accordingly.

I'm also confused why the EA model wasn't speced for the house. If you're planning on buying more at some point, buy some S4 PAR EA's, use them as your house lights, and use the MCM models on stage.


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No more heat off a Fresnel than a S-4 Par for all intensive purposes. None are ideal fixture efficiency wise - or as equipment stuff one would rather be using on stage or be better used on stage, rather than as a perminant architectural house light but both/all would work. Both fixtures by definition are also "temporary install" equipment and not to be used for a perminant install type of application audience lighting might imply. At one point I used pinspots for audience lighting. Audience got a kick out of having to move their programs to the beam of light in order to read them, much less in going in and out of the beams of light - this as a one time only novel idea and not a constant thing. Had another stadium that was thinking audience blinders for house lights - this until they learned about the lamp life of a normal PAR 36 audience blinder.

As long as sufficient illuminanance levels are met in the audience by way of distribution and coverage, anything that directs the light should work including Lekos. Frequently scoops are used even. Have a customer that does frosted 1Kw frosted 20,000 hour 16" scoops to light their church .. . what is it audience area..., than some stage and studio DKZ lamps for the wash on the diasis.

In audience lighting, given "temporary install" is wavered on the S-4 type fixture, this would be a good application for the extended life 120v lamps.
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