Use industrial fluorescent banks instead of Kino?

[erik_ande_85]

Hi!

I'm looking for a cheaper alternative to Kino Flo.

I just saw that you can buy regular fluorescent 2 banks used in inudstrial places.

2x58w that must be something similar to the output of kino flo's?

Let's say i would 2 of these. And then put them together.


Another question:

How about fluorescent light bulbs? A kit like this one is pretty cheap.

http://cgi.ebay.com/3000-Watt-VIDEO...ltDomain_0?hash=item1c0fcb9525#ht_2886wt_1165

How is it compared to the kinos?


Yes, I think Kino is to expensive and I'm trying to come up with a cheaper solutionrogar-Happy(DBG):

 

[Richard Crowley]

The two key features of the Kino products are:

• BALLAST: They use a high-frequency electronic ballast to avoid any problems with "strobing" from power mains-frequency artifacts
• COLOR TEMP: They have tubes made for them with a special formulation of phosphors to create a much more accurate color balance (CRI Color Rendering Index)

You can find high-frequency ballasts even in $19 shop lights from Home Depot. There does not appear to be any magic in the Kino ballasts.

OTOH, you cannot find good high-CRI fluorescent tubes at your typical vendors. You need to look specifically for tubes which are designed for better CRI. Many people think that a CRI factor of 90 is the minimum desirable, but it depends on the cost/benefit ratio of your particular situation.

Other than the name and reputation, the other thing you are paying for with Kino (and other commercial products) is the packaging, form factor, accessories, etc.

I have successfully used $19 "shop light" fixtures from Home Depot and fastened a "Baby Nail" on the back.

(6" Baby Nail -On Plate. 5/8" diameter. CAT NO 429085)

Then I could attach them to industry-standard light stands with a "grip head".

(Matthews Mini Grip Head. CAT# 350584)

The illustrations are from FilmTools, my favorite vendor for grip gadgets.

 

[erik_ande_85]

Thanks for your answer!

Seems pretty important to have a ballast and accruate color temps.


How about the ebay link I posted, the fluorescent light bulbs?

Could they be used in the same way as kino banks? A bit softer maybe?


Alos one more question:

the lights on ebay runs on 110v. I'm in Sweden and we have 230v 50hz. What kind of converter do I need to use US imported lights in Sweden?

 

[Richard Crowley]

The light kit on eBay that you referred to uses small screw-in compact fluorescent (CFL) "bulbs". It is more difficult to find good color-balanced (high-CRI) bulbs in that CFL size. The concept of a large diffusing "tent" is a convenient form of making a large-area "soft light" portable. I'm not sure the total output from one of those would be the same as four regular tubes which are around 1m in length?

Powering any kind of lamps from 230V should be easy enough. Fluorescent ballasts (and whole lamp fixtures) are available in all the popular mains voltages. I don't see why that would be an issue. Just be sure to use devices rated for your power mains voltage. The fluorescent tubes themselves are the same wherever you use them. It is the ballast that is made for 120V or 230V (or whatever power mains voltage you have). You should not need to import items from the US. The same kinds of tubes, bulbs, fixtures, ballasts, etc. should be available in Europe.

ALL fluorescent tubes, bulbs, etc. require a ballast. The earlier generations of ballasts operated on the mains frequency (50Hz in your country). That caused the tubes to flicker and could be a problem for shooting film or video. That is why the Kino fixtures use the high-frequency electronic ballasts. The high-frequency electronic ballasts are also being more popular in general purpose lamp fixtures that you would put in your home or shop. Because they are becoming less expensive to make (and ship) than the old "heavy-iron" ballasts.

 

[nejuicer]

You can find high-frequency ballasts even in $19 shop lights from Home Depot. There does not appear to be any magic in the Kino ballasts.

There does not appear to be any truth to that statement either. You get what you pay for. Inexpensive high frequency fluorescent ballasts can have another type of flicker problem called an “eratz ripple.” Even though the ballasts put out a high-frequency cycle, that cycle stacks 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.

To drive their tubes as brightly as possible, Kino Flo ballasts also send a higher output current to the lamps, than standard high frequency electronic fluorescent ballasts. 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.

All fluorescent fixtures are a good choice for operation on small portable generators in the limited sense that they use a quarter of the power of a comparable tungsten soft light. However, the ballasts of conventional “shop lights” (as well as the older style Kino fixtures) that use the T-12 tubes are not Power Factor Corrected (PFC) and return harmonic currents into the power stream. When used in quantity, they can constitute a source of considerable harmonic noise. For this reason, on their website Kino Flo cautions users of their older style fixtures that also use T-12 tubes, that the ballasts “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”.) 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.

Put simply, when you plug a single 4’ - 4 tube “shop 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 the “shop 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 T-12 “shop light” fixtures into conventional portable generators. As a comparison of the oscilloscope shots above and below indicate, the return of harmonic currents by conventional T-12 ballasts can generate voltage distortion in the power stream. 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 by a non-PFC electronic ballast (HMI or Kino) will result 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.​

Given the adverse effect of just a few conventional electronic fluorescent ballasts on a 5500W conventional generator, I wondered what the accumulative effect would be on the generator of a typical lighting load made up of only non-PFC HMI & Fluorescent fixtures? To see, 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 below is startling.

The adverse effects of the severe harmonic noise 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 T-12 Fluorescents on conventional portable gas generators. Harmonic noise of this magnitude can also damage HD digital cinema production equipment, create ground loops, and possibly create radio frequency (RF) interference. 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 Fixture ballasts is that 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 electronic ballasts. The harmonic distortion created by 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 Kinos 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 Kino Flo ballasts, 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 HMI and Kino ballasts 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 ballasts, 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 Kino ballasts – they enable you to operate more lights, more affordably, on locations where there is no house power.

Guy Holt, Gaffer, ScreenLight & Grip , Boston

 

[nejuicer]

Other than the name and reputation, the other thing you are paying for with Kino (and other commercial products) is the packaging, form factor, accessories, etc.

Besides the ballasts, the “form factor” and “accessories” of Kino Flo fixtures make them well worth the extra money. Again, the Kino Flo Parabeam 400 is a good example. What distinguishes the Parabeam fixtures from the hardware store “shop light” is their throw, power efficiency, and the innovative accessories Kino Flo makes available for the fixtures that enhance their production capabilities for lighting dramatic scenes. Accessories include barndoors, a gel frame, a diffusion panel, and Honeycomb Louvers.

If you are lighting a movie, you will be better served by a ParaBeam 400 fixture than a “shop light” because they use computer aided designed (CAD) parabolic reflectors to focus their light output where it is needed most for lighting dramatic scenes - at a medium distance – making it a better key source. If you compare the photometric tables of the Parabeam 400 with those of even a Kino Flo Diva 400 (which uses the same four lamps), you will notice that at 16’ the Parabeam 400 puts out almost three times the light level (28FC) than the Diva 400 (10FC) even though they both use the same tubes. In fact a Parabeam 400 generates as much light at 16’ as the 4’ 8-Tube Kino Flathead 80 fixture, yet uses less than a quarter of the power – making it an ideal light to operate on a portable generator.

Not only do the Parabeam fixtures have more throw than a “shop light”, but they are also easily controlled – an essential requirement in a movie light. Parabeam fixtures are controlled by interchanging Kino Flos’ innovative Honeycomb Louvers. Louvers are available in 90, 60 and 45 degrees. Swapping louvers provides beam control similar to that of swapping lenses on an HMI Par. These features enhance the production capabilities of the Parabeam fixtures and make them suitable to serve as a key or backlight source where conventional fluorescent “shop light” fixtures will spill all over a set and are therefore only suited to serve as fill sources. These special features that distinguish a Kino Flo Parabeam from conventional “shop lights” make them well worth the extra money.

Guy Holt, Gaffer, ScreenLight & Grip , Boston