S4 vs Older Strands

Jankers

Member
Hello.

I have a group of S4's and group of old strands (i've heard them referred to as the 2331s?), and I will be using both for an upcoming show.

Now, I know that a S4 will outshoot one of these any day of the week. However, I am wondering if anybody can tell me what would happen if the S4's had 120v 575 long life lamps? The last time I used them, they seemed incredibly dim, and I could swear that the Strands were brighter. Can anybody shed some light on this for me.

Thank you!
 
What sort of lamps are you using in the Strands? It's hard to compare without that information.
This sounds like a post for the big man... but us lamp civilians will take a stab at it first.

Personally, I've been very happy with the long life S4 lamps.
 
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The Strands have 1000w FELs. I forgot to mention, the S4s are a mix of 19 degrees, 26 degrees and 36 degrees, and the Strands seem just slightly narrower than the 26 degrees, which I believe makes them 6X12s. It's the 26s and really the 36s that I noticed the problem with.
 
Are those the Strand/Century lekos from the early 80's? My old middle school had those. It was a K-12 private school, so they had a pretty nice theatre. It was built in I think 83 or 84, and every fixture was Strand/Century. Since then they've bought some Altman Shakes, S4 Pars, and a couple MR16 zip strips. I believe they switched over to HX600 or 601 lamps on the old Strands to conserve dimmers.

Anyway, back to the topic....The long life 120V HPL puts out a bit more than 12,000 lumens. Since the voltage at the raceway will most likely be less than 120V, expect less than rated output from the 120V lamps. The high output HPL's do about 16,000 lumens and have a higher color temperature. If you want to go middle of the road, the question becomes whether to go with long life 115V lamps and run them a little over voltage, or go with 120V high output lamps and run them a little under voltage.

Check the lamps in your S4's. Read the stamp on the metal or ceramic heat sink, it will tell you the wattage, voltage, and if it is a high output or long life lamp. A "C" after the wattage denotes a high output lamp, an "X" after the wattage denotes a long life lamp. Example for a 115v, 575w, high output lamp: HPL115V/575WC. The voltage and wattage may be reversed...I don't have a lamp in front of me right now to confirm. If the lamp is a 120V long life then replace it with something brighter. Next step is to check the bench focus. I've never seen an S4 with a hole in the field so big that it encompasses the entire beam, but I guess you could check for a grossly out of whack bench focus. Sharp focus your unit and rotate the small bench focus knob on the end cap and try to notice if the brightness of the beam changes. You may also want to make sure the reflector and lenses are good. Swap the end cap from one of your 19's (or whatever the ones without the problem are) to one of the 36's and see if it improves. You may also want to swap lens tubes as well to make sure your lenses aren't too dirty or something.
 
I believe those 1000 Watt FEL's are rated at about 27,500 lumens. While they are far less efficient than an S4... you are still looking at an initial lumen output of 15,000 more than the 12,360 lumen HPL-X. The folks at ETC were amazing when they designed the S4 but they weren't miracle workers... so it's not surprising that your Strands seem a little brighter.

What about switching the S4's to the 750 watt long life lamps... the Osram 750X's put out 16,400 lumens so they are the same as a standard 575 watt lamp. However since it's a long life the lamp life is rated at 1,500 hours instead of the 300 on a standard 575. If that doesn't do it the straight 750 watt lamp boasts a whopping 21,000 lumens which will kill your Strands.

Negative of this move is that you are probably going to burn gel a lot faster.

Also all that stuff that Fosstech said about bench focus and cleaning is a great idea too.

How are we doing Ship?
 
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I assume your old Strand units are their axial units? We use a bunch of those all the time, I still have 53 in service (though we are hoping to retire them and replace them them soon). Our Source Fours easily outperform the Strand units any day. As has been the subject of many threads here, the FEL is a very inefficient lamp. I believe that if you replace it with the HX-600 or 601 you will get the same output at just over half the wattage (and you are less prone to getting burs on your forearms during focus). I am still trying to get to the bottom of the very large box of FEL's that I have, after which I will be switching to another lamp. Also, the strand units should have a plate on the outside of the lens tube that says what lens it is. You may have to pull the lens out of the instrument to find the tag.

As was mentioned, check the bench focus of your source fours. Also, make sure the lenses are clean. Check to make sure the lenses are in correctly (unless you know that the lens tubes were never taken apart for cleaning or anything). Measure the voltage at the raceways/drob boxes in your theatre, and choose the appropriate lamps (as mentioned above). It is true though, the Strand units do put out a nice beam, they should look amazingly similar to the source four (at least in my experience).
 
(i've heard them referred to as the 2331s?)

#2331 & 3232 (Radial) ERS: EGG, EGC

My lamp/fixture cross reference notes might be off but I believe the above is a #2331. Photometrics handbook confirms this. Hey, that's the light my high school had. Had some in college also.

If it's taking a FEL is it possible that it's a #2230 or #2213 if 20 to 29 degree (6x12) instead?


"How are we doing ship?" Hmm..., keep working on it. No offense meant of course and well done for the most part in stock type concepts or answers - bench focus / 120v/115v concepts in lighting. I at least am not seeing much of an answer given the initial question which admiditly is broad in concept of what element of the stated lamps are flexible in type, not much useful for answer about balancing the beams between fixtures to make them look the same.

(here goes the broken record of my stated opinion about lamps....)
This except (in not making anyone stand out but noting it for clarification and hope) for the above HX-600 / HX-601 concept of the next lamps one will go to after the box of FEL's are done... that's about 10 years out of date in what lamp to choose next. This in the hope that nobody has to deal with the fragile HX-600 also inefficient filament in comparison to the HPL, and gets to upgrade his fixtures instead to the better lamps out there. Try a Osram HPR for high output general use that can out-punch a S-4 in more intense harder edge beam, a GLC for pattern projection in being smaller yet in filament, or #6981P for 750w high output, or GLE for long life. Big mistake Osram made in doing the HPR lamp was that they did it with a FLK/HX-600 filament (more rugged perhaps.) If they did the HPR with a GLC filament, it would be atop the charts as better than the HPL lamp. As it is now, good lamp, out punches in beam the HPL but graphically not better. The GLC is not as refined as the HPL but is really close. Optically it's the lamp one wants to use at 575w for pattern projection.
 
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I'm not attempting to answer the question or muddy the waters. Hopefully the debate/discussion will go on further given I didn't do much below. I'm hoping it further sparks noting stuff and debate if not a fixture shoot off and more clarification.


Below is all rough estimation on my part.

In going back to the questions, a Strand fixture optically speaking is no slouch of a lighting fixture. It’s well known no matter what era to be a darned good fixture. With a FEL... that’s just bulk lighting with some extent of it getting out the gate.

Outshoot..... pull up in a search of the forum the letters HPR. This amongst past discussions of FEL lamps, #6982P lamps etc.

Could as mentioned be a lens or bench focus thing but as also mentioned, also the 120v HPL lamp is operating in a condition under it’s rated voltage thus the luminous output and color temperature drop while it’s lamp life goes up. (Gonna last a really long time.) A 120v long life lamp is even more so in already having less output. Overall, such a HPL 575w/120vX lamp should be considered for an architectural install (lobby lighting) only and consider it about as powerful as a 375w/115v extended life HPL realistically. Pick one or the other extended life or 120v for a S-4 fixture, or up the wattage in keeping both than deal with the amber shift in a HPL 750w/120vX in hoping for similar output to a 575w lamp at a much lower color temperature. Again, gonna last forever but most likely won’t be as bright in color temperature as the FEL.

Lots of times color temperature will confuse the eye into thinking it’s more illumination - don’t look persay at how blue/white the light appears to be, more look at the coverage and intensity of the beam.

So, in the initial question... yep, if you used a HPL 575w/120vX lamp in a S-4 verses a FEL (aak!) in the Strand, the Strand I would tend to think outshoot the S-4. If radial Leko, a EGC would be almost about as bright as a HPL 575w/120vX overall in a shoot out given well bench focused fixtures, and the EGG to be a brighter with even more output. That’s my estimation in taking into account the huge hole in the reflector and less efficient lamps. The 750w EGG might match up to a say HPL 575w/115vX by way of slightly less output is my guess.

If FEL verses HPL 575w/115vC, it should be a balanced fight to some extent given Strand vs. ETC. The ETC with this lamp should eek out more light given the FEL, but loose out against a HPR or #6981P.

Back again to the original question, in mixing the S-4 using a HPL 575w/120vX lamp with a axial series of Leko, I might match it up with a EHD lamp given the Strand fixture. Should be fairly close fixture to fixture, or perhaps a GLA but the GLA should out punch the HPL. The G.E. #37404 HX-603 575w/120v is the only real similar lamp but it’s long gone in being discontinued. Nothing available in the FLK/HX-600 type lamps that are long life and 120v these days. A long life FLK/LL (a non-ANSI lamp) or HX-601 might if the EHD is not similar enough would be the next choice for a matching lamp to the HPL 575w/120v/X, otherwise a HX-400 would possibly match up also. Lots of variation in filament efficiency, lamp life, color temperature and overall output to factor in.

Hope I didn’t confuse or it helped. Refine the question perhaps more, are you attempting to match the Strands to the HPL 575w/120vX lamps or attempting to get a lamp for the S-4 that will match up to the despised FEL lamp? This or are both available for swapping out say in balancing lamp life with output between them?


Beyond this, quick and simple... use the more dim/amber light for the amber light, the blue one for the blue lighting.
 
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You know Ship, if I actually paid attention to some of your other lamp posts...
 

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