Well, in discussions with the school principal (who has a minor in theater) we have come to the conclusion that although LED technology is very promising, it still is not ready to replace the "old fashioned" theater lighting.

Direct comparisons with the beat up old par-can lighting we currently use demonstrates that the 64 LED Pro nowhere near matches the light output and beam focus of a traditional 300 watt medium flood incandescent stage light.


I want to do a fair test, so first here is the test area (one of the school computer labs) which is a fairly long space:


And here is the equipment being tested, two brand new 64B LED Pro, and a really beat up old PAR-can containing a GE 300watt medium flood incandescent lamp:


Here is the far wall, with the room lights on, where we will be doing the comparisons:


So, first we will use a single 64B LED Pro in the dark. It looks okay but this isn't a good test since the camera is auto-adjusting exposure.


We need to directly compare it to the incandescent flood, and... oh dear.. this is not good. The flood has a very wide beam due to the filament shape, but the overall intensity far outstrips the output of the 64B LED Pro. The camera is adjusting its white balance to match the brighter light source, which reveals the LED output to be very blue in comparison:


Well, what happens if we turn on the second 64B LED Pro and shine them side by side to match the incandescent spot size? This still doesn't really match the incandescent flood output:


It appears I may need up to four times as many LED Pro 64, to match just one of the old 300watt lamps. Since we currently already have 24 300 watt lamps, I will end up with a sea of 96 of these just to get to the same light output level. At the full retail price of $400, that is $38,400 worth of 64B LED Pro's -- um, I don't think we can afford that.

It is unfortunate but it appears LED technology is still not ready to take the place of the old high-wattage par fixtures.

-----------------------

It looks to me like part of the problem is that the LED Pro does not focus its light output well enough. There is a significant amount of light being dimly cast in a large halo around the fixture, which is more apparent if I direct the beam towards the ceiling:


The incandescent does not exhibit this same fringe scattering, and all light seems directed towards the front. What illumination that is visible appears to be backscatter from the main beam spot on the wall:


To test this scatter theory, here I am standing in front of the 64B LED Pro to see how much of a shadow I can cast on the wall. If what I am seeing is only backscatter then I won't cast a shadow, but alas there is a very sharp shadow visible:


Repeating this test with the 300watt medium flood, there is almost nothing for a shadow unless I get very close to the beam spot, showing this is mostly backscatter:


For some reason, due to the shape of the LEDs, the light output is dim in most of the side field, but then suddenly intensifies with sharp points of light at approximately 70 degrees to the side of the beam.


- Dale

Dale,

That was an interesting comparison. Do you know what the rating in lumens for the various light sources used?

Max

The incandescent lamp is a General Electric, 300 watt, 120 volt, PAR-56, Sealed-beam reflector, Mogul base, Medium flood, but it does not have an exact model number.

This page looks exactly like it, so it is probably 3840 lumens, with a 2000 hr lifespan:
http://www.elightbulbs.com/cat...BaseCSE&prod=GL20836

- Dale

Considering you can get around 50 or more 64 LED Pros on a single 15 amp circuit, well, then the cost savings jumps up quite a bit as power consumption is still down.

I find myself haveing the following issue with my LED 64 Pros: I can never get the time to properly set them. Why? Lack of on-staff skill around to do it. So, I don't get the throw I need. I've had great results with the 8, but I really want to double it to 16.

It may be worth looking into the Elation LED offerings. Yes, more money, but more oriented for higher output. Might be the way to go.

In comparison, LED would be the way to go. It is more effecient and power saving, not to mention alot less heat.

At a cost of $300 to $400 per LED Pro it doesn't make sense to buy them on the basis of "energy savings".

The purchase goal should be color changing flexibility, because the efficiency savings difference vs the dim LED light output level requires many more fixtures. Needing so many more fixtures to make up for the lower output is going to at least 12 years to pay itself off.


=============================================

What is the price difference between LED technology and traditional incandescent technology and how long does it take to "pay back" the difference in energy savings?


For a bank of 8 300 watt incandescents you need:
- 8 PAR-54 cans, about $35 each
- 8 300w medium-flood lamps, about $25 each, lasts 2000 hrs
- 1 20amp dimmer pack (DP DMX 20L), about $200 each

Total hardware cost: $680
8 300 watt lamps use 2400 watts total.

--------------------------------------------

For equivalent light output, it appears I need four times as many lights, though I'll be generous for this analysis and say 3 times more, so:
- 24 64B LED Pro - $400 each, full retail

Total hardware cost: $9600

Each LED Pro appears to use about 45 watts at maximum draw, so total circuit load is 45 * 24 = 1080 watts

==============================================


Assuming an energy cost of 10 cents per kilowatt hour

8 incandescent floods: $0.24 per hour of operation, 100% output

24 LED Pros: $0.11 per hour of operation, 100% output

Incandescent flood cost per hour assuming 2000 hr life per lamp: (8 * $0.0125) / hour



Time to break even vs incandescents is:
$480 initial + (8 * $0.0125 * hours) + ($0.24 * hours) = $9600 + ($0.11 * hours)

Solve for hours of use: $0.23 * hours = $8920

Time to break even on energy savings with $400 LED Pro:
38,782 hours, 1615 days, 4.4 years

============================================


I see the LED Pro can be found for $300 online, so the math for that is:
$480 initial + (8 * $0.0125 * hours) + ($0.24 * hours) = $7200 + ($0.11 * hours)

($0.23 * hours = $6520)

Time to break even on energy savings with $300 LED Pro:
28,347 hours, 1181 days, 3.2 years


This assumes 24 hour usage which you will almost never do. The lights will be lucky to see 25% of this amount of use (6 hours every day), which drags out the payback to four times as long -- 17 years @ $400 per LED Pro, or 12 years at $300 per LED Pro.

So if you're buying these on the basis of energy savings alone, you'd better hope nothing breaks in those many years before payback.


(Math typo fixed, 8 incandescent fixtures replaced every 2000 hrs)

This message has been edited. Last edited by: DMahalko,

Chris,
i agree with you,LED lights are more oriented for higher output.Even though they are just a bit more expensive,they are totally worth it!! LED is the way to go!! i highly recommend replacing incandescent lights with LED's.

Nice analysis. I don't have the same numbers.

But you're leaving out a few things:
Someone has to go up and change bulbs. That's manpower costs. And the latter or system you're gonna use(or hopefully someone else) that has to go change them. But, those aren't super super big costs.

Also I forgot to mention: I can't explain WHY, maybe it's not even real, but for some reason my eye seems to give me the view that if I use the gel holder, I get better focus and less halo. I could be full of crap on that one. I don't see how the focus could be affected, but I could see how it can remove the halo effect.

Also, don't forget to real more of the lead in to the discussion. Dean is showing rather graphically, and as honestly as his photo hardware will allow, as fair as possible a comparison between a conventional vs LED fixture. While I may agree that his shootout may not be 100% fair to both, I think his tests are done in the spirit of being open minded and fair. While he's not using scientific measuring equipment, I think his tests are relatively fair and real-world. And sure, he ain't a big fan of the LED's at the moment, and I'd say with what he posted, I'd say he's got good cause.

I on the other hand am quite pleased(as are my clients) with my 64 LED Pros. Although, I'd be happier with twice as many to cover a larger area and just flat out more light.

I am just left with the impression from Dean that he's being as open minded as he can be and he's trying to test as fair as he can. If his opinion varies from mine, then that's how it goes. I understand his application, and I can sort of see what he's going after. I do agree with some of the things he's mentioned in those observations as well. But I just couldn't test it, and hence could not communicate it.

So I finally got over here, lol.

I will have to add my findings to yours DMahalko. I have comparisons of AMDJ 64 Pro vs Opti RGBs vs DLED 36s, vs Opti 30 RGBs vs 750w Source 4 ParNels. Also have some stuff on LED diffusion vs no diffusion as well as an Impression vs a Power Spot 575 IE. Getting ready to compare some Opti RBG Tris against S4 ParNels next. I will have to add my findings to yours.

While LEDs aren't cost effective intensity per dollar vs conventional lights yet, they offer many benefits that conventionals don't have. They can do just about any color in the rainbow with DMX control vs one color of a gelled conventional. You can add things like color scrollers to conventionals, but that is still limited color choices, and they can't cross fade between colors like LEDs can. Then you have things like Seachangers that give conventionals CMY, but they cost even more then color scrollers. So adding color scrollers and Seachangers makes conventionals cost just as much or more then higher powered LED based products.

LEDs can also strobe, faster then strobe lights even. This is a very useful feature for me and others as well I am sure. Power consumption is also greatly reduced compared to conventionals, and we all run into less then ideal power situations. Being able to run say 100+ Opti 30 RGBs off a 20 amp can be a great help sometimes. LEDs also don't interfere with audio and video like conventionals and dimmers can. Being able to share power when necessary with audio and/or video is sometimes a real blessing in pinches.

The other two downfalls I can think of with LEDs vs conventionals is that you need to run DMX and power to them vs just power and data to the dimmer rack/packs. The other major thing is they take up more channels of DMX then conventionals. Sure, you can dumb them down to one channel mode, but that defeats one of the main reasons I use them in the first place, being able to make whatever color I want, when I want. So you have to have higher channel count controllers to use them to full effect. For me, this is rarely an issue since most consoles I use have unlimited channels, for others, this can be a real issue since those consoles cost more and are an added expense to already more expensive LED fixtures.

Edit: See here for LED Diffusion vs none in DLED 36s

Edit 2: See here for DLED36 vs Opti 30 RGB

This message has been edited. Last edited by: SerraAva,

Well, one of the things we have to also look at is, quite frankly, the brand.

A Par64 is a Par64, conventional. Period. Yes, there are issues as to quality and durability and yes, you do get what you pay for.

Looking at ADJ vs say Elation, you pay MORE for Elation and you get way more. Compare the ADJ Par64 LED's vs the Elation offerings. Whole different animal practically.

But something you do bring up is power, but think about it. If you're running socapex up your trusses and terminated in either edison or stage pins, well, you're already doing the same thing anyways. You're just extending the rack mounted dimmers up an expensive and durable cable to plug into somehting else. It's really just power anyways. So, you could simply re-do those for straight power and then string DMX-512 signaling up there. We're not re-inventing the wheel, but we could just toss in a power strip or two and get the same sort of thing as well.

Channels: Irrelevant. You can always reclaim channels by matching for lights that are expected to do the same thing. For the channel limited, this is an issue. But if you're channel limited, then you're already causing your own problems. This goes back to what you're saying that you don't have these problems because you're using higher end stuff.

For me, the power savings is the real issue, and even if that means I have to DOUBLE my investment in the 64 LED Pros, then so be it. 8 150-watt Par38's runs me 1200 watts per tree(8 on a T-Bar, 4 top, 4 bottom). 2 trees: 2400 watts. Granted, I won't be running all 4 channels all the time, which saves me 600 watts, which puts me safe in the 15-amp range, BARELY!! But the Par38's have a super wide spread.... so, it's like "gee, ADJ, come on, sell me an LED bulb for my Par38's that behaves just like a traditional medium to wide beam incadescent so I can get those 32 Par38's I have on a low-power plan!!!"

More research, more research.

You know what might be needed? A lens for the LED's. This should help focus the lights. I mean, after all, isn't the front of most Par bulbs a lense of some sort to help concentrate the light? Maybe an add-on or retrofit? Maybe it won't add the brightness, but might help get a more event result?

You do indeed get what you pay for, that doesn't change no matter the industry. However, for some LEDs just simply aren't cost effective. What will look better, 100 Opti Pars or 100 P56 LEDs? (Includes cost for dimmers) That always has to be weighed and considered.

A power cable is a power cable. However, not everyone can afford multi, especially since the break ins and outs can cost as much or more then the cable its self. Regular old 12 gauge or even 14/16 gauge is much cheaper. Multi just makes life easier, not really more cost effective unless you are talking large shows with a lot of runs.

Channels are actually extremely relevant. Last theatre show I did, I had a 48 rack of Sensors, 9 Opti 30 RGBs, 2 DLED36s, and 2 Power Spot 575 IEs. The console was an ETC 72/144, so channel count wasn't an issue with 244 channels. However, if they had the 24/48 with only 96 total channels, I couldn't have done the show like I did. All the gear without the dimmers was 98 channels, and I needed individual control over each LED and PS. Even putting the LEDs in 3 channel mode would not have helped, since 65+48 is 113 and again needed individual control over too many dimmers. I am actually designing a show now where I have this issue. I want to use a couple of DS575Es and a couple of VL1000 shuttering models, but console is Express 24/48. The movers along go over 96 channels and then I have 96 channels of dimming on top of that. Not enough cash to bring in my Hog for the show either, so I think I might have to ditch all the conventionals I am renting.

As for LED beam spread, anything from AMDJ just simply isn't powerful enough yet. For example, I can tell you that an Opti RGB is actually brighter then a DLED36 with the frost filter in it since it is such a smaller beam. However, but the 45 degree lens in the Opti RGB and it is weaker then an Opti 30 RGB with half the LEDs though again, a bigger beam.

As for focusing LEDs, well that is tricky too. To focus them, you apparently have to bounce them off of a series of mirrors to get a focusable beam. This in turn, however, drops output of the light since some is wasted in the reflection as well as some spill lose. So A single source 20w LED is keeping up with a 250w arc lamp, but it takes a 200w single source LED to keep up with a 575w discharge lamp apparently.

It is also not research as much as cost. They have LEDs out as powerful as 200w, but they are not cheap at all. The other thing is plasma lamps are being researched now too. They are even smaller then LEDs, use even less power, but put out even more light and last just as long. So the LED revolution might be a short one with regards to how long lamps have been around.

Serra Welcome To the ADJ forums! That's right jingles is here too. HAHA! Thanks for helping out here too.
Sincerely,

I know RadioHead did a major tour using all LED's, so it proves that LED CAN be used in big concerts. But is it practical? Personally, I can't stand Radiohead, I'd rather hear a showerhead, but that's a whole other matter.

When I did my cost analysis for conventional Par64's(with dimmer packs, DMX-DP20L's) vs LED's(64 LED Pros), the case was a winner for the conventionals, but by a small margin. It was an easy decision for me to just move ahead on LED as I had all the colors I needed and enough wash to make it work. I think we're talking a sub-$100 total difference of 8 Par64's with 2 dimmers, vs 8 64 LED Pros.

Looking at the brands, we have to admit that Elation is the "step above", and in some cases way above American DJ. But the marketplaces are also totally different as well. ADJ is selling to small people(mainly) and those with limited budgets. Elation customers tend to have deeper pockets. It's not a fair comparison.

As far as not bringing in your Hog console, well, we differ there. I'm constantly using my big A&H console for shows(audio, please!), even for small crap. Why? I just prefer to work on it. Well, plus it adequately has the tools I need on it. Your reasons for not bringing the right gear are your own business things. Hey, if the marketplace in your area lets you get away with doing things like that, crap, I wish this area would smack itself in the head and get like that. Here they want cheap, crap and above all cheap. Quality doesn't factor in. So, I'm giving great for cheap. Right now, any 2-bit upstart with a stolen Par38, a DJ mixer and an amp with 2 speakers things they are a sound production company and concert promoter and screwing things up left and right.

I think with your comparison of the 20w LED keeping up with a 250w arc lamp, vs a 200w single source LED keeping up with a 575 discharge lamp, aren't arcs and discharge lamps different? Of course, the math used for audio doesn't match the math for lighting and wattage comparisons, as to get those extra 5db in audio, we have to double the total power(which can become quite painful in many ways, mainly to the power draw and pocket book!).

I don't think ADJ is going to catch up to Elation. I think what will happen is that as ADJ stuff gets "brighter", in turn so will the Elation stuff for the same reasons: technolgoy improves while cost drops. So, both companies impove existing products at the same price. Of course Elation is going to stay ahead, it costs. Back to the "you get what you pay for" thing.

As far as plasma is concerned, I'm not into that technology yet, just not a lighting guy. I would assume that if it is as robust as LED can be, then it should be a good thing. LED is just starting to prove itself in most circles. This is remindng me of the DVD then BluRay/HDDVD war that went on. Sounds like once again the consumer is gonna be the test platform. Fortunately, I passed on that whole fiasco and waited for the dust to settle. With lighting at least, why wait? We can stick with traditionals/conventions until this all gets settled out.

True, Radiohead did an all LED tour. The designers had one headache after another on that tour. LEDs just simply aren't powerful enough yet, and this proved it to many designers thinking of trying the same thing.

Cost wise, that is way off. 8 Par 64s with lens kits list for $75 a piece. The DP-DMX20Ls list for $260 a piece. That is $1120 total for 8 Par 64s with lenses and 2 dimmers. P64 LED Pros list for $400 a piece or $3200 for 8. That is a cost difference of $2080. Lamp replacements would take years to make up that cost difference. Also, by the time it is made up, the LEDs will be way out of date and something much more powerful will be out.

A budget is a budget. It doesn't matter if you have $1,000 to spend or $100,000 to spend. Cost is almost never irrelevant. So if with my $1,000 I choose to get 2 Opti 30 RGBs or 2 P64 LED Pros, that is on me or my client who rented such.

I can't justify loaning out a Hog for 2 full weeks for nothing. If once in those 2 weeks it goes out, I am no longer upside down. Smaller, single day events, yes I will take it out if clients are paying for it. Makes my life easier. Same with my boss. He will take his tour rack full of Drawmer punch gates and comps along with his Midas Vernoa or Siena for one day gigs. They sound so much better then other consoles he can take out. However, if he has a job that is paying for it, it goes there, pure and simple. Also, sometimes space allowed simply doesn't let him bring out a 32 or 40 channel desk. Sometimes it is simply a mix wizard and that's it.

In this industry, if you truly are good, people will be willing to pay for you. I can tell you that our line array (4 boxes a side and 2 double 18s a side) generally goes out for around $2,500 a day. There are people that sell it cheaper, but don't get the jobs because they are just that, cheaper. Build a firm client base and prove you are worth it. If something breaks on the line array only going out on $1,000 a day, then the company is upside down money wise, and that is just bad business. I would rather see that line array sit and be in the black for a smaller PA then in the red. You are trying to move up market, not down.

Discharge and arc lamps are the same thing. You are right that it isn't a linear progression. Audio technically is, it is just an exponential progression is all. Actually, sound is more math based then lighting is when you get down to it.

Why wait? Well if that is the case, why buy DMX based products? It is a dead format technically. ArtNet and other Ethernet based control formats are replacing it. Allows for two way communication between fixtures and console, no more need to address anymore, Ethernet cable is even more robust and can carry more data (Hog Net can do 64 universes with one Ethernet cable). Simply put, the industry is slow to change. The Source 4 leko has been the standard now since 1992. Before that, the Altman 360Q was the standard for 20 some odd years. Then before that, it was a Klegie something or another. Conventionals aren't going to go away any time soon. People just don't have the money to retro fit spaces for LED lights, just like people don't have the money to use ArtNet over DMX, yet. However, DMX will be around for years and years to come.

Ops, didn't see you reply in there jingles. Lol, yea. I was sitting around bored at a medical convention last Friday in NYC and just drifted over here. I now am an expert on Asthma, ways to treat and control it lol.