10 Bulb CFL Brute (Sample Video)

[Richard Andrewski]

This is another reason I haven't been too keen on making these types of fixtures. The main surface area emanating light is not allowed to do its job since they are all sticking out at a 90 degree angle from the fixture and no flat surface reflector behind them will do all that much good. In effect each of the bulbs is radiating its best area of light into each other rather than out away from the fixture as it should. A much better design would be several par type reflectors which will make the fixture much larger of course so it may lose some of its compactness which I think is one reason people like these types.

 

[Robert Niessner]

I did a quick test with a single bulb and it shows clearly a darker spot in the center - I got the brightest spot when angling the bulb by 45 degrees.

 

[Andrew McCarrick]

Can I ask why CFLs? Why not LEDs (http://earthled.com)? Especially since CFLs contain mercury vapor.

 

[Ryan E. Walters]

Can I ask why CFLs? Why not LEDs (http://earthled.com)? Especially since CFLs contain mercury vapor.

That is a good point. I'll have to look through those LED options. Right now I've gone with CFL's due to price / output / availability. The 10 65w CFL's only draw a total of 650w's and give me an output of almost 3k of light at a cost of about $200 for the bulbs. So far I have yet to be able to find a comparable LED solution.

I have always thought that it has been a funny thing to market CFL's as "green". Sure they last longer then the incandescent bulb, but they contain a lot more harmful chemicals in them - that cannot be a good thing ...

 

[Dustin Cross]

This is another reason I haven't been too keen on making these types of fixtures.....

Richard,

Size wouldn't bother me, to a point. If you built a 4'x4' fixture with 9 of your 200w CFL, each in a mirrored cone to send out the most light. The cones could be 16" wide at the widest and I am sure there is a point where the angle is maximised. The unit would be about 18-24" deep. So kinda big, but not to bad for a light that puts out 1800w of CFL light (maybe 7000w of potential output) on a single curcuit. Put 4x4 diffusion (or custom 4x4 softbox) in front of it and you have a very powerful light, that isn't small, but is manageable. Needs a combo stand, but if you need that much light, you should get a big stand.

I also think you could pack 16 of your 200x CFL bulbs in the same 48x48x18 housing with less angle on the cone. Run it off two 20amp curcuits and you get an amazing 3600w of CFL light (maybe 12000w of potential output).

I think as long as the beam coming off the cones is focused about two feet in front to the housing where the 4x4 frame (or softbox) is you would get max output.

What do you guys think?

I am currently building a 12 200x cfl fixture, using my old Flolight 330 housing. I'll send pics and stats when it is done.


Dusty

 

[Andrew McCarrick]

That is a good point. I'll have to look through those LED options. Right now I've gone with CFL's due to price / output / availability. The 10 65w CFL's only draw a total of 650w's and give me an output of almost 3k of light at a cost of about $200 for the bulbs. So far I have yet to be able to find a comparable LED solution.

Well LEDs last about 4 times longer than CFLs... so they do have a higher up front cost, but they last longer, use less electricity than CFLs, contain no mercury, and are made so they can't shatter.

ZetaLux from EarthLED is:
Power Consumption: 7 Watts Max (6 Watts Typical)
Input Voltage: 90~277 V AC (Worldwide Capable)
Luminous Flux: 450 (Cool White), 350 (Warm White)
Color Temperature: 3000 K (Warm), 6000 K (Cool)
CRI: 75 - Cool , 80 - Warm
Beam Angle – 180 degrees overall
Operating Temperature Range:
-22°~176° F (-30°~80° C)

EvoLux would be another option at 13 watts with about the equivalent output of a 100 watt incadescent.
http://earthled.com/evolux-led-light-bulb.html

 

[Dustin Cross]

I just measured Richards 200w CFL softbox light and it is only 16" deep with the bulb in it. So you could do 48x48x16 wide mirrored cones and I would buy it. The other nice thing about that design is it protects the bulbs. With the softbox you have to take the bulb out and store in it a box to protect it.


Thanks
Dusty

 

[DCC Erickson]

hi tech meets low tech

hi tech meets low tech

9 ceramic leviton bases in a Mac tower. Nice aluminum housing. sockets still weigh a lot. Wanted to be able to use a variety of hardware store bulbs, so can't fit more than nine in. Wired hastily for a shoot, diffusing through an old shower curtain liner. Didn't melt. 8 150w floods from Savers at $2 per. At least I won't have to worry about paying for Snow Leopard.

 

[Ryan E. Walters]

Well LEDs last about 4 times longer than CFLs... so they do have a higher up front cost, but they last longer, use less electricity than CFLs, contain no mercury, and are made so they can't shatter.

Great points for sure- but in the end they are still only 13w / 100w eq. To get the same output of the 10 65w CFL's I'd have to get 28 of those bulbs, and rig them all together some how. That would not be a small light ... Once these lights get stronger or smaller, I think it will be a more viable option.

 

[Ryan E. Walters]

9 ceramic leviton bases in a Mac tower. Nice aluminum housing. sockets still weigh a lot. Wanted to be able to use a variety of hardware store bulbs, so can't fit more than nine in. Wired hastily for a shoot, diffusing through an old shower curtain liner. Didn't melt. 8 150w floods from Savers at $2 per. At least I won't have to worry about paying for Snow Leopard.

LOL! I love it- that is VERY creative.

 

[Ryan E. Walters]

This is another reason I haven't been too keen on making these types of fixtures. The main surface area emanating light is not allowed to do its job since they are all sticking out at a 90 degree angle from the fixture and no flat surface reflector behind them will do all that much good. In effect each of the bulbs is radiating its best area of light into each other rather than out away from the fixture as it should. A much better design would be several par type reflectors which will make the fixture much larger of course so it may lose some of its compactness which I think is one reason people like these types.

If for no other reason the lack of profit from doing this is a good enough reason to not make them. (The one I built did not come in a lot under the price of buying the pre-made one. ($100 vs $150) ).

Par reflectors sound like a good idea ...

 

[Richard Andrewski]

I just measured Richards 200w CFL softbox light and it is only 16" deep with the bulb in it. So you could do 48x48x16 wide mirrored cones and I would buy it. The other nice thing about that design is it protects the bulbs. With the softbox you have to take the bulb out and store in it a box to protect it.

You realize that's a monster fixture and the yoke to hold it up would have to be incredibly hefty to keep angle and keep it from sagging down. The parabolas have to be rather large to get any good light out of each bulb. I think it becomes ungainly. One thing to experiment with would be some kind of fixture that contained several 16" x 16" softboxes each with its own 200w bulb in it. I think thats the minimum size for each reflector. Then you've got less weight. You have to build a frame then that can turn on angle and that's the challenging part.

The only way to protect the bulbs is with a total metal fixture and even if you leave them in there, there's still a pretty good chance you could break them all with just the right jolt against something or someone dropping it. Plus we're talking about something so big it would be hard to haul around and would take two people to carry it. I'm just not sure its practical.

 

[Guy Bryan Holt]

So I just modified a 16 bulb CFL light to make it fit 10 65w CFL's for an equivalent 2,750w of light output at a draw of only 650w!

How is the flicker? I have noticed some CFLs flicker at unexpected frequencies - ie. you would expect 60Hz and be able to dial it our with a 144degree (1/60) shutter.

I have given up on DIY heads like this because I have found that there is usually some magic in the established brands that make them worth the money, otherwise they would not exist as companies. For instance, Kino Flo could not exist as a company if anyone could make a homemade version of a fluorescent light that was just as good for production applications. This “CFL Brute” is a good example of what I mean. Besides the well established CRI issues, CFL bulbs have a number of drawbacks that make them less suitable for production applications. First off, as Brent correctly observed above, they can have a type of flicker problem called an “eratz ripple.” Even though the bulbs operate at high-frequency, the cycles can stack to create a lower frequency waveform which causes the light to pulsate. In a number of incidents, 24p video cameras and film cameras operating within a flicker-free window have picked up flicker from the “eratz ripple” effect. When making your own fluorescent soft banks or using solid-state high frequency ballasts for built-in set practical fluorescent light fixtures, it is necessary to shoot tests with the ballast you plan to use to make sure you will not get an “eratz ripple.” 
Kino Flo fixtures, on the other hand, use high frequency electronic ballasts that run at specific high frequencies that eliminate the generation of an “eratz ripple” (most at 25 kHz , the Parabeam Light at greater than 30 kHz) resulting in flicker free operation at any frame rate or shutter setting. Kino Flo ballasts also incorporates advanced electronic circuitry so that they will ignite a lamp instantly, even when cold, requiring no warm up time.

Compared to DIY fixtures using T-12 tubes, Kino Flo ballasts send a higher output current to the lamps, than residential high frequency electronic fluorescent ballasts, to drive their tubes as brightly as possible. For this reason only Kino Flo True Match lamps should be used in Kino Flo fixtures. The phosphors in Kino Flo True Match Lamps have been reformulated to match the spectral sensitivity curves of film and digital imaging equipment at the higher milliamps at which the ballasts operate. If that weren’t enough “magic,” the newer Kino Flo fixtures that use the biax tubes use ballasts that include Power Factor Correction (PFC) circuitry. As it does in HMI ballasts, this advanced electronics contributes to a more economical use of power than conventional electronic ballasts and reduces the return of harmonic currents into the power stream. For example, a Kino Flo Parabeam 400 draws less than half of the power (2 Amps) of a comparable 4’ – 4 Bank “shop light” (4.6 Amps). While this nearly 3 amp difference is not a major consideration when using house power, it can make a difference when your power is coming from a portable generator because you can use two Parabeam 400s for the same power as a 4’ – 4 Bank “shop light”. With a Power Factor Rating of over .9, the Parabeam 400 fixtures are especially well suited for use on small portable generators.

The fourth and final magical ingredient to Kino Flo ballasts pertains to the newer Biax fixtures (Diva, Parabeam, Vistabeam, Barfly) and is probably the most difficult to understand because it has to do with the vagaries associated with the load put on portable generators. If you haven't already, I would suggest you read the article I wrote for our company newsletter on the use of portable generators in motion picture lighting. In it I cover some of the basic electrical engineering principles behind harmonic distortion and how it can adversely effect generators. The article is available on our website.

There is a popular misconception that all fluorescent fixtures, CFLs in particular, are a good choice for operation on small portable generators because they use a quarter of the power of a comparable tungsten soft light. However, the ballasts of conventional “shop lights” and CFL bulbs are not Power Factor Corrected (PFC) and return harmonic currents into the power stream. For this reason, on their website Lowell warns about their compact fluorescent (CFL) fixture, the Lowel Ego, that: “The lamps may cause interference with radios, cordless phones, televisions, and remote controls. If interference occurs, move this product away from the device or move to a different outlet” (http://www.lowel.com/ego/lamp_info.html.) The same harmonic currents that can cause RF interference, also cause fixtures using the bulbs to draw double the current on the neutral of the electrical system powering them. For a detailed explanation for why harmonic currents cause unusually high neutral returns see my article on the use of portable generators in motion picture production available on our website.

In the residential lighting applications for which CFLs are designed, harmonic currents are less of a concern than they are in motion picture lighting applications. Put simply, when you plug a CFL “Brute Light” into a wall outlet you need not be concerned about harmonic currents. As is the case with non-PFC HMI ballasts discussed elsewhere in this forum, the impedance of the electrical path from the power plant is so low, the distortion of the original voltage waveform so small (1-3%), and the plant capacity so large in comparison to the load of the one light, that the inherently noisy load of a CFL “Brute Light” will not affect the voltage at the distribution bus.

Left: Grid Power w/ no load and a THD of less then 3%. Center: Conventional Generator w/ no load and a THD of 17-19%. Right: Inverter Generator w/ no load and a THD of 2.5%.​

It is, however, an all together different situation when plugging the same fixture into conventional portable generators. Like the non-pfc ballasts of the older style Kino fixtures that use T-12 ballasts (the Single, Double, & 4 Bank Fixtures, the Wall-o-Lite fixture, as well as the Image 20, 40, & 80 fixtures), CFL bulbs return harmonic currents into the power stream that can generate voltage distortion. As a comparison of the oscilloscope shots above and below indicate, given the large sub-transient impedance of conventional portable generators, and the fact that the original supply voltage waveform of conventional generators is appreciably distorted (a THD of 17-19%) to begin with , you have a situation where the return of any harmonic currents, whether by a CFL or non-PFC electronic ballast (HMI or Kino), results in significant waveform distortion of the voltage in the distribution system.

Left: Grid Power w/ Kino Flo Wall-o-Lite. Center: Conventional AVR Power w/ Kino Flo Wall-o-Lite. Right: Inverter Power w/ Kino Flo Wall-o-Lite.​

The generation of harmonic currents by production equipment should be eliminated whenever possible, otherwise it can build to a point where it will have an adverse effect upon other equipment running on the same power. For example, for my newsletter article I ran a package consisting of two Arri 1200 HMI Par Pluses (with standard Arri non-PFC electronic ballasts) in addition to a 4’ – 10 tube Kino Flo Wall-o-Lite (with T-12 Ballasts) on a Honda EX5500 (a conventional generator). And, for the sake of comparison, I ran a comparable package but with power factor corrected electronic ballasts on our modified EU6500is (an inverter generator.) The difference between the resulting waveforms was startling. Where I am out of space, I will have to explain the difference in a subsequent post.

Guy Holt, Gaffer, ScreenLight & Grip , Boston

 

[Guy Bryan Holt]

The difference between the resulting waveforms was startling. Where I am out of space, I will have to explain the difference in a subsequent post.

The adverse effects of the severe harmonic noise generated by non-pfc light fixtures (exhibited below left), can take the form of overheating and failing equipment, efficiency losses, circuit breaker trips, excessive current on the neutral return, and instability of the generator’s voltage and frequency. For these reasons it has never been possible to reliably operate more than a couple of 1200W HMIs along with non-pfc Fluorescents on conventional portable gas generators. Harmonic noise of this magnitude can also damage HD digital cinema production equipment, create ground loops, and create radio frequency (RF) interference that Lowell warns about. For a detailed explanation for why this is, see my article on the use of portable generators in motion picture production available on our website.

Left: Conventional generator power w/ pkg. of non-PFC Elec. HMI Ballasts & Kino Flo Wall-o-Lite. Right: Inverter generator power w/ Pkg. of PFC Elec. Ballasts & Kino Flo Parabeam 400.​

It is worth noting in the oscilloscope shots above that the distortion of the voltage waveform is considerably less in the case of the inverter Honda EU6500is generator (far right) than that of the conventional Honda EX5500 generator (left.) The reason for this is that, as discussed at length in my article, the original waveform of the power generated by the EU6500is (an inverter generator) has less harmonic distortion at the outset than that originally generated by a EX5500 (conventional generator.) For this reason, when your lighting package consists predominantly of light sources, like HMI and Fluorescent lights, it is important to have power factor correction (PFC) circuitry in the ballasts (HMI & Kino) and operate them on inverter generators like our modified Honda EU6500is. The magic to Kino Biax Fixtures (the Diva, Parabeam, Vista Beam, & Barfly fixtures) that can not be easily replicated in a DIY fixture is that their ballasts are power factor corrected. Their improved power factor, when combined with the nearly pure power waveform of inverter generators, makes it possible to power larger lights, or more smaller lights, on a small portable gas generator than has been possible before.

Wide Shot of Night exterior scene lit with our HD P&P Pkg.​

For example, the substantial reduction in line noise that results from using PFC Kino and HMI ballasts on the nearly pure power waveform of an inverter generator creates a new math when it comes to calculating the load you can put on a generator. In the past we had to de-rate portable gas generators because of the inherent short comings of conventional generators with AVR and Frequency governing systems when dealing with the harmonic noise of non-PFC HMI and Fluorescent fixtures. The harmonic distortion created by their non-PFC ballasts reacting poorly with the distorted power waveform of conventional AVR generators (as evident in the oscilloscope shots above) limited the number HMIs and Fluorescents you could power on a portable generator to 60% of their rated capacity (4200Watts on a 6500W Generator).

The PFC 2.5 & 1.2 HMI Pars, PFC 800w Joker HMI, Kino Flo Flat Head 80, 2 ParaBeam 400s, and a ParaBeam 200 of our HD P&P Pkg. powered by our modified Honda EU6500is through our 60A Full Power Transformer/Distro​

But now, that inverter generators have virtually no inherent harmonic distortion or sub-transient impedance and power factor correction (PFC) is available in both small HMI and the Kino Flo Biax fixtures, this conventional wisdom regarding portable gas generators no longer holds true. Where before you could not operate more than a couple 1200W HMIs with non-PFC ballasts on a conventional generator because of the consequent harmonic distortion, now according to the new math of low line noise, you can load an inverter generator to capacity. And if the generator is our modified EU6500is inverter generator, you will be able to run a continuous load of up to 7500W as long as your HMIs and Kinos are Power Factor Corrected.

A Distro System consisting of a 60A Full Power Transformer/Distro, 2-60A GPC (Bates) Splitters, 2-60A Woodhead Box distributes power from a modified Honda EU6500is. Even though the generator is 100' away to reduce noise, plug-in points remain conveniently close to set.​

According to this new math, when you add up the incremental savings in power to be gained by using only PFC Lights, and combine it with the pure waveform of inverter generators, you can run more lights on a portable gas generator than has been possible before. For example, the 7500W capacity of our modified Honda EU6500is Inverter Generator powered a lighting package for a recent Red shoot (see production stills above) that consisted of a PFC 2.5kw HMI Par, PFC 1200, & 800 HMI Pars, a couple of Kino Flo ParaBeam 400s, a couple of ParaBeam 200s, and a Flat Head 80. Given the light sensitivity of HD cameras, this is all the light needed to light even a large night exterior. There in lies the final magic of the new Kino fixtures – they enable you to operate more lights, more affordably, on locations where there is no house power.

Guy Holt, Gaffer, ScreenLight & Grip , Boston

 

[Nick Gardner]

OK seriously, stop posting the same shit over and over and over in every thread with a reference to electricity.

 

[Joe G.]

In the middle of catching up on this post today, my two PAR 64 can lights arrived, bought from ebay.

Temp link:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200433798189&ssPageName=ADME:X:AAQ:US:1123

They mount with a screw clamp onto any pipe or table top, 2x4, etc. Perfect for a simple vertical pipe in cement bucket "stand" as I already made.

$25 bucks each!

I'm looking at these bulbs:

http://www.bulbamerica.com/OSRAM-SY...luPAR64-PAR64-par64-VNSP-56017--3952-prod.htm

Only $24 for a 1K spotlight bulb, 3200K. "400000" candle power -- is that lumens?

Anyone know if there will be a difference between the "very narrow" and "flood" bulbs, when sitting way down in an aluminum tube?

 

[Erik Bien]

Only $24 for a 1K spotlight bulb, 3200K. "400000" candle power -- is that lumens?

No. Multiply candlepower by 12.57 to get lumens. Here's an explanation of the relationship between lumens, footcandles and candlepower.

Anyone know if there will be a difference between the "very narrow" and "flood" bulbs, when sitting way down in an aluminum tube?

Yes — essentially all of the technology of a sealed-beam PAR is in the globe itself (which is why the fixtures are so cheap). The 1K VNSP (Very Narrow SPot, aka 'firestarters') globes have an especially narrow field angle, so they throw a very tight, very bright oval-shaped beam (here are some Stage Lighting Fixture Tables which are helpful for comparing coverage vs. intensity).

 

[Guy Bryan Holt]

OK seriously, stop posting the same shit over and over and over in every thread with a reference to electricity.

It may seem like I'm posting the "same shit over and over" to those who don't bother to read the posts. As far as I can recall, I have never posted on power factor correction as it pertains to fluorescent fixtures in general. Granted, I have posted extensively on the harmonic noise generated by HMIs. I am now posting on the harmonic noise generated by fluorescent fixtures because it is a commonly overlooked problem and one that is becoming more prevalent.

For instance, how many readers of this forum knew that most fluorescent lights used in production are not power factor corrected and can be a source of considerable harmonic noise in a power stream. For example, the older style Kino Flo fixtures that use the T-12 tubes (the Single, Double, and 4 Bank Fixtures, the Wall-o-Lite, Flathead 80, and the Image 20, 40, & 80 fixtures) are not power factor corrected and return so much harmonic noise to the power stream that when used in quantity, as in studio chroma key productions, they can constitute a serious problem. For this reason, Kino Flo cautions users, on their website: “Kino Flo ballasts are generally not power factor corrected. They will draw double the current on the neutral from what is being drawn on the two hot legs. On large installations it may be necessary to double your neutral run so as not to exceed your cable capacity.”( FAQ “Why is the neutral drawing more than the hot leg” at http://www.kinoflo.com/FYI/FAQs.htm#2) Don’t assume that all newer fluorescent fixtures using Biax tubes are power factor corrected. For instance the non-dimmable ballasts used by Lowell in the Fluo-Tec Studio, E-Studio, Caselite fixtures have a power factor similar to that of a non-pfc electronic HMI ballast of .7 (http://www.lowel.com/fluotec/technical.html.) And, of their compact fluorescent (CFL) fixture, the Lowel Ego, Lowell warns: “The lamps may cause interference with radios, cordless phones, televisions, and remote controls. If interference occurs, move this product away from the device or move to a different outlet”( http://www.lowel.com/ego/lamp_info.html.)

The generation of harmonic currents by production equipment should be eliminated whenever possible, otherwise harmonic noise can build to a point where it will have an adverse effect upon other equipment running on the same power. In fact, a viscous cycle can get started. The more harmonic orders that are generated, the more distorted the power supplied by the generator becomes. The more distorted the power waveform becomes, the more harmonic currents are thrown back into the electrical distribution system, which in turn, creates additional voltage distortion. In this fashion, something akin to a feedback loop can get started. Very often, the operation of electrical equipment may seem normal, but under a certain combination of conditions, the impact of harmonics is enhanced with unpredictable results.

Harmonic distortion is becoming a more prevalent problem because some of the power generation equipment we use on set was not designed to deal with the abundance of non-linear loads like electronic HMI and Fluorescent ballasts in use today. Running incandescent lights on generators was never a problem because as purely resistive loads they didn’t create harmonic currents. While the inductive reactance of magnetic ballasts running on generators created voltage spikes, they operated pretty reliably if the generator was equipped with an AC frequency governor. The problem began with the increasing use of non-linear lighting loads, like electronic HMI and Fluorescent ballasts, that generate harmonic currents. The problem is being further compounded by the increasing prevalence on set of sophisticated electronic production equipment like computers, hard drives, and HD monitors which require clean stable power to operate, but are themselves sources of harmonic distortion. Where in the past, much attention was given to generator features such as automatic voltage regulation, speed regulation and AC Frequency; given the increasing prevalence of harmonic currents and the problems they cause, an increasingly more important feature today is the quality of the generated waveform which is why I stress it in many of my posts.

I have put many hours into researching generators, the harmonic noise generated by both HMI & Fluorescent electronic ballasts, and the effect it has on set power. I have spent many more hours trying to put that down in writing so that others can benefit by it as well. I have made this information available for free in this forum and on our website (available at http://www.screenlightandgrip.com/html/emailnewsletter_generators.html) rather than selling it to a trade magazine or publisher that would make you pay for it. If it seems like I am “posting the same shit over and over and over in every thread,” it is because harmonic noise is generated by all kinds of production equipment. And where it can lead to disastrous situations it is something to keep in mind. Now you can either deny it is a problem and be worse off for it; or you can accept it and your awareness of these effects will help you to build systems that avoid or mitigate problems on set.

Guy Holt, Gaffer, ScreenLight & Grip , Boston

 

[Nick Gardner]

I choose not to play.

 

[Richard Andrewski]

It may seem like I'm posting the "same shit over and over" to those who don't bother to read the posts. As far as I can recall, I have never posted on power factor correction as it pertains to fluorescent fixtures in general. ScreenLight & Grip , Boston

Your partner Eileen Ryan did post pretty much the same though:

http://www.reduser.net/forum/showthread.php?t=37524&page=2


I definitely think we got it. Repeated messages like this are called advertising and Jason Ramsey handles agreements for this site. You might want to contact him about that.