ELC vs. EVC lamps - What gives?

Hello, newbie here looking for advice.

I've been putting together a low cost backlighting system for a rock band, no critical lighting involved, just an "ooh pretty lights" kinda thing. Main thrust here is remotely aimable, crisp, bright colors for mood. Using a low output hazer for beam definition.

Most of the fixtures I've seen in the sub $500 range use an ELC lamp, but I've seen a few with EVC's or EHJ's. In looking at bulb specs, it looks like EVC's and EHJ's have about 10 times the lumen output, cost less and last longer.

So why are ELC's so prevalent in this price range? It seems to me that if a decent reflector is used, an EVC fixture would bury an ELC fixture.

I must be missing some info here, any takers?
I see that an EVC is 3200k and an ELC is usually around 3400k, so the ELC would look whiter, cleaner.

Your experience then, is that this 200k difference in temperature has a pretty drastic effect? I guess I'm just going to have to see them side by side to understand fully. Thanks for the input.
I am certain that ship will come along before too long and will be able to give you the details you were looking for.
The ELC would appear warmer in color when placed next to a EVC. Thats really all there is to it.

Depends on what your looking to do with the lamp. When i had Altmans and Source 4's i put the Source 4's on my cool wash cause they appear cooler to begin with and I would be able to get my desired effect easier.
Chris15 said:
I am certain that ship will come along before too long and will be able to give you the details you were looking for.

Ah', thanks for the knod. You do of course realize that the difference between EVC and ELC is what got me into studying lamps for in part my living don't you? My old 1986 GE catalog I innitially was using didn't mention one had a reflector and one didn't. Imagine the problems there in what otherwise for listings is the same lamp for all intensive purposes.
Chris15 said:
That would be rather an important difference.

Urr yea, but given I came from the theater industry and suddenly was thrown into being the buyer of lamps for the entertainment industry, who will have known. Probably still have a few of the origional 100 ELC lamps I bought and kept buying for a while in stock seven years later.

Bear with me, there is useful info in this sort of pet lamp to follow once I open up my notes on the lamp types - lots of them on the subject and efficiencies.

For now if you check out Pro sound web http://forums.delphiforums.com/lightnetwork/messages?msg=11245.9
you can see there was a time where I still didn't have it all understood and made one mistake in advice. On the other hand, I think by way abuse sent my way, I think I held myself up fairly well in direct response.
"Ah', thanks for the knod. You do of course realize that the difference between EVC and ELC is what got me into studying lamps for in part my living don't you?"

Perfect, looks like I came to the right place!

So what's your take, ship, do we go with 8000 extra lumens or 200 extra kelvins for the most defined beam and color saturation?
polterbike said:
Perfect, looks like I came to the right place!

I suspect that you would be able to find answers to all your questions here, on all aspects of technical theatre. Welcome.

And as far as lamp questions go, Ship will know, or know in which book to look it up, I mean who else do you know that has $100K of lamps in stock.
$100K? Were I to venture a rough guess in this touring season not yet ended since last touring season except for a lot more video shoots requiring all new lamps, I would say that the figure would be a bit out of whack and I'm still yet to know it's rough figure. Buying a lot of expensive lamps is not really anything however, that knowing the difference between one brand and another and what else is on the market is what I strive for learning.

Not saying I am an expert at other than acquiring what I need as if any other stage hand where thrust into doing what they need to do. When it comes down to it, I have never installed a trackspot lamp and would have to get out a manual just to address it. I buy the lamps for fixtures and our resale needs as if stock market trader or as if I were buying sewing machines. Granted I know as much as I can about what I buy, but am at some base sense still a tech person doing the best I can given no formal education other than what I have studied on my own.

For EVC lamps on the other hand, over the last year or two, their sales have dropped way down. Used to sell somewhere around 600 per year, this year it's probably in the 250 range. Don't know why, I just buy them. Still buying the Osram EVC instead of Phillips or other brand of EVC or HES QT-8500 which has the specs of the Osram lamp instead of that of their Phillips maker. Phillips explains it as a OEM product thus their own lamp does not match that of what they make for High End. Yep, the Phillips vendor rep thought this was kind of silly in taking one of many notes a year or so ago during the last face to face visit.

Reason I'm holding off on a true reply about this EVC lamp type is that I think there is a lamp out htere that might be a better option but don't remember what it is.

Beyond this and as promissed, while the lamps are very similar and vendor dependant, there is a very specific difference between a MR-16 based lamp that has it's reflector pre-focused on the filament and that of a fixture that has a hole in it's reflector large enough to fit a lamp with some tolerance into it so as to project the same light. That's probably the major difference that is noted in output. Also candlepower is a reference to the collected by the fixture and focused light beam by way of reflector or fixture with lamp installed as opposed to luminous output in 360 degrees that is Luminous output.

Kind of an apples and oranges type of thing and no real way to compare the two other than by way of fixture each lamp is installed into specifications by way of end result.

ELC lamp is rated for 50 hours, so is the EVC by way of memory. There might be newer types of each but for the most part the ELC is the more cost efficient and probably light efficient type of lamp to install. By way of lamp life, I would probably go with the Phillips ELC/5H lamp over that of the current Martin ELC/10H version offered or that of the 7H or 8H or 3H. Each #H represents the number of hundreds of hours a lamp is rated for. On the other hand, for a extension in life, you loose luminous output and color temperature as a rule. The 500 hour lamp while it's specific specifications are not as with any lamp of this type easy to get, probably the best lamp you could balance output for life with for the fixture.

As for the EVC lamp/QT-8500 lamp, while different brand, I recently looked into it. I did not find any between the Osram EVC and High End QT-8500 with better output at that wattage. There were other lamps available and I think some that possibly will have a better exchange of output for lamp life options, but none so far brighter that I could find for a customer so far by way of lamp specs on the lamps available.

Difference in fixture output much less cost of lamps on the other hand isn't something I have compared. To this extent I'm holding off so far. What specific fixtures are being compared and what's the output of the fixtures given the same beam angle that is listed by way of the manufacturers?

Once one has this end result by way of fixture and lens, one can take the specified lamp tested for that output and convert the replacement lamps's expected output thus come up with a figure. But as opposed to comparing a FLK verses GLC lamp, a MR-16 lamp verses capsule lamp that for the most part is the same if not in most ways the same does not really have a reference point other than lamp life and color temperature. The EVC by way of memory has a better color temperature dependant upon brand by way of memory but possibly not also by way of new technology. I believe I remember some xenon/halogen lamps on the market these days that are in the 55K or above range for color temperature by way of internal color correction. Don't remember what lamps they were on the other hand pre-color corrected.
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Benefits of this lamp:
1) Pre-focused alignment of filament to center of the reflector. Very hard to screw up the bench focus with this type of lamp as long as it's fully seated or in it's bracket.

2) The reflector chances are will be both cleaner in not having years of build up on it which even if kept clean does still coat the reflector with time. It would also be more refined by way of not having to have a hole in it's center rear that not only is large enough to fit a lamp in, also has some loss of light extra due to the tolerance and room needed in leaving a gap between lamp and reflector. About 15% of the light from a lamp is lost out of the hole between lamp and reflector.

ELC lamps are for the most part (few exceptions) no matter the brand all 3,400K in color temperature (almost as hot as you can get before the filament burns up) and have a 50 hour lamp life. Output when listed at all normally is within the 800 to 900 Lumen or 800 and 1,500 Lux range dependant upon brand and which catalog the specifications were listed in. Ushio for instance lists both in Lux - the one having a lens seemingly is loosing 700 Lux due to it. You most likely don't need lensed lamps inside a fixture. (Such specifications for all brands change once in a while catalog to catalog for the same brand.)

Beyond this, they have a focus point to the light of about 31.7mm away from the lamp.

Most have a very important note to follow which would also effect the usefulness of the lighting fixture it's installed into:
Burn Base Down to Horizontal. This means the lamp cannot be pointing upwards or up side down. If this note is not followed the lamp's filament will probably stretch out and break due to a lack of support in that direction or more likely the lamp won't cool properly and blow thru it's pinch seal. The only exception for this seems to be the Osram brand of ELC lamp which notes any burning position. Wiko didn't note a burn position but it would probably follow suite with GE, Phillips and Ushio in the above note. With the advent of P-3 pinch seal Technology and other companies following suite with their own improved pinch tech., many of these lamps in the last year or two may have been upgraded to universal burn also. Before you buy a specific brand, check the brand's website to see what the up to date status of the burn position is should this be a concern. Most of the long life ELC lamps have had this upgrade.

ELC lamps are also more cost efficiently available in 300hr, 500hr, 700hr (I remember 800hr from somewhere) and 1,000 hour now.

There is an exchange (short of new technology compensating for it) in lamp design. Mostly, to achieve a longer lamp life you must give up something else or normally a combination of things. Voltage of the lamp could be raised, luminous output could be dropped down and or color temperature can also be dropped. Given the above improvements to pinch seal technology on the other hand, it might be possible that while some things did have to change some, due to the lamp now being able to burn hotter, other things could be adjusted to compensate and keep the output and color temperature the same.

In other words while normally a long life lamp will either be of a higher voltage which adjusts the color temperature and luminous output downward by way of the full voltage not heating the filament up all the way. Or the filament is doped to boost the life in exchange for less color temperature and output.(Doping is a term in reference to the combination of metals making up what the filament is composed of. In doping say in a HPL long life verses high output lamp, different more resistant metals which don't burn as hot but last longer are used and some times a thicker and or larger filament is used.)

In long life lamps available, the real data on the lamp more than at times perhaps wishful thinking is normally not available. Phillips for instance for their ELC/10H lamp in their initial specification of the lamp listed it at 3,100K in color temperature. As of 3/03 they changed it by way of typo or upgrade to 3,400K the same as the 50 hour lamp. The initial listing of the lamp's color temperature for this 1,000 hour lamp seems more realistic. No Luminous output data is available for this lamp. This is the lamp Martin is currently selling their fixtures using that lamp with. I stock them for resale but don't use them. That much life would reduce the output of the fixture. Martin's specifications for their fixtures is based on the ELC lamp and have not been upgraded to cite the expected lower output of the long life lamp.

Note when judging one fixture to another what the lamp this test data was tested with before you put absolute faith into the fixture's output.

Osram in their ELC/7x lamp lists a color temperature of 3,200K which sounds about right and also lists 475 Lumens in output. Seems a bit low and this might be an inaccurate specification.

Possibly the best balance of lamp life to output is the Philips ELC/5H. I have four listings from the catalogs on this lamp since it came out. Half list it as 3,400K and the other half at 3,100K. I have never measured which is accurate but at one point did compare the output of the 5H to a Ushio 3x. The Phillips did seem brighter so lamp life is not an absolute figure for expecting the longer the life, the dimmer the lamp. This is the lamp Martin used to recommend before the 10H came out.

Wiko also sells a ELC/5X. It also lists a 3,400K color temperature. Interesting listing for the lamp, must be a typo given only 50 hours of lamp life listed and a note of 120v operation +/- 76 hours. Given this, I'm not sure what the difference between this lamp, their ELC and their ELC/E is other than the other lamps don't have the note. I expect the 5x lamp is a 500 hour lamp and it's a typo on their part.

Osram, Phillips and Ushio all sell a ELC/3 which would be 300 hours and the same in lamp life as the EVC. Phillips does not list a color temperature for this lamp but does list a 960Lux - roughly 2/3 that of the 50hr version. Osram lists it's color temperature at 3,250K with 550Lux and Ushio at 3,400K which as above was not realistic. Ushio also lists 900 Lumen / 960 Lux for output.

From above it's fairly certain that while there probably is differences in technology and brands, all brands of lamp probably also list a lot of differing information much of it inaccurate. In other words, none of the specifications on the above lamps provides enough accurate information to say what lamp is best.

Finally there is one somewhat new JER 24-250 Phillips lamp out there which might be a ELC, or it might be it's own lamp. Doesn't list it's color temperature but does list 900 Lux for output and 50 hours in life. It's also base down to horizontal.
The EVC lamp has a lot more information provided about it. It’s also heavily dependant upon brand for what’s best or cost effective. Remember that this lamp while it seems much brighter in luminous output is taking for a figure the brightness 360 degrees around the lamp as opposed to the light coming out of a 2" reflector in one direction. Once this lamp is installed into a reflector, the output will also drop. How much depends upon the fixture.

Benefits over that of the ELC, or by Lif code the M-33.
1)Cheaper Lamps
2)Longer specified lamp hours for the high output version of the lamp.

High End buys their QT-8500 lamp as a OEM product from Phillips. Phillips does not sell this lamp to anyone but High End. IT’s not a cheap lamp but is a 300 hour lamp and the one High End specifies for use. This lamp has 3,200K in color temperature and 9,000 Lumens in output.

The Phillips EVC lamp lists 3,200K but only 8,400 Lumens in output as compared to the QT-8500. 300hrs

Ushio lists their EVC lamp at 3,400K in color temperature and 8,400 Lumens in output. 300hrs. This data could make it a very good lamp if one would like one with average output but a higher color temperature.

GE doesn’t seem to be selling this lamp any longer as far as I can tell.
Wiko lists their EVC at 3,200K, 8,400 Lumens but only 200 hours in life.

Osram possibly has the best version of this lamp. It’s listed at 3,200K in color temperature, 9,000 Lumens in output and 300 hours in life. In other words, it’s the same basic lamp as the QT-8500.

There is three alternate long life lamps available on the market should 300 hours not be enough.

Reflekto (owned by Ushio) sells the 250T4.25Q/CL24v. Reflekto is a very good quality company. It does not list color temperature but does list 4,500 Lumens in output and 2,000 hours in life.

EYE ( Iwasaki Lighting International ) has the JC24v250w20H/G2. Been selling it for years as a long life EVC lamp - the customers using it are more concerned about having to change lamps frequently than the loss of output. Color Temperature is 3,000K, Output is 5,750 Lumens, and lamp life is 2,000 hours.

Dura Lamp (a fairly new company on the market) has the JC250 24v GY6.35/CL. I don’t know much about this brand or lamp yet. Color Temperature is 3,000K, Output is 5,700 Lumens and life is an astounding 3,000 hours. If it is all it is said to be, this would be a very cost effective lamp even if 2/3 the output for 10x the life.

There is other options available in installing higher wattage 275 and 300w lamps into the fixture but due to potential heat issues, this would not be recommended without a lot of testing.

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