Guy Holt

Here are some recent threads on lighting at night that may be of help: http://www.cinematography.com/index.php?showtopic=58618 http://www.cinematography.com/index.php?showtopic=61155&page=2&hl=%2Bday+%2Bfor+%2Bnight&do=findComment&comment=399691 http://www.cinematography.com/index.php?showtopic=62140&p=401790 Good Luck, Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

While Marc makes some very good points, and is even correct in theory on some, in realty things are very different. So different that I do not agree with the conclusions he draws. Where my response pertains to how to access more power through 240V receptacles using a step-down transformer than it does to the original post, I have started a new thread where I address his points one at a time. The new thread is available at Accessing more power through 240V receptacles. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

Marc Roessler wrote: It (line-loss) is really no issue with 240V as long as your cables are thick enough, and that's really the only clean solution to the problem. Long runs? - Thicker cables! Again, Marc is correct in theory, but not in practice. In the iRobot Spot, given as an example in the other thread (use this link), half the circuit consists of the house wiring, so it is simply not an option in realty to go to a larger cable size to reduce line-loss. In the case of portable generators, most of the voltage drop is on the generator’s output and not on the cable run (generators will drop nearly 10V under full load). Using a larger cable size will not compensate for voltage drop on a generator, but switching taps on a transformer will. And, as we saw above, the slight increase (2.8A) in the current drawn by a 5000W load by boosting the voltage by means of the transformer’s taps is negligible. You might ask yourself, why not operate at the lower voltage (109.7V) if it means drawing less current (37.3A.) The reason is that low voltage on set can cause problems such as reduced efficiency and excessive heat in equipment, unnecessary additional load on the generator, and a dramatic shift in the color temperature and in the output of lights. For example, the effect of line-loss on tungsten lights can be dramatic because their output falls off geometrically as the voltage decreases. For example a 1k lamp operating at 90% rated voltage (108V) produces about 68% of its normal light output - your 1kw lamp is now a 650W lamp. But, that is not all, as the light intensity decreases, so does the Kelvin color temperature of the emitted light. In the case of fluorescents, HMIs, and LEDs, because their power supplies are typically of a “constant power” type, they will draw more current as the line voltage decreases in order to maintain constant power to the lamp. With an Apparent Power of 2290VA, the Arri 1200 Par that drew 19A at 120V (2290VA/120V = 19.08A) will draw 20.87A amps at 109.7V (2290VA/109.7V = 20.87A.) Since the Arri Ballast has an operating range from 90-125V, it is not likely that the ballast will shut off from under voltage, but it is very likely that the 20A breaker providing over current protection to the Edison U-Ground receptacle it is plugged into will trip and shut the light off. In the case of generator output, voltage loss translates into an exponential loss in power. That is because, if you double the ampere load on the cable, the voltage drop also doubles, but the power loss increases fourfold. What this means is that when a distribution system has a large voltage drop, the performance of the generator (its maximum effective load) is reduced. Given these consequences of voltage drop the negligible increase in current drawn by boosting voltage by means of a transformer’s taps is well worth it IMOH. Use this link for details about other benefits to be gained by powering lights off of 240V with a step-down transformer. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

Cont. from above: For the third trial, I compensated for the appreciable voltage drop over the 350 feet of twist-lock extension between the generator and the Transformer/Distro by using the “Voltage Select” switch to boost voltage on the secondary side by 5% to compensate for the 5V line-loss. Where I have run out of space, I will pick up this post later.With the voltage boost, our 5000W incandescent load drew 42.5A (21.25A x 2= 42.5A) at a voltage of 119.2 (see meter screen capture below.) For a fourth trial, I created additional voltage drop through line-loss by adding another 200 feet of twist-lock extension between the generator and the Transformer/Distro. Without using the “Voltage Select” capability to boost voltage to compensate for the line-loss, our 5000W incandescent load drew 37.3A (18.65A x 2= 37.3A) at a reduced voltage of 109.7V (see meter screen capture below.) For a fifth trial, I compensated for the additional voltage drop over the now 550 feet of twist-lock extension between the generator and the Transformer/Distro by using the “Voltage Select” switch to boost voltage on the secondary side by 10% to compensate for the 9.2V line-loss. With the two stage voltage boost, our 5000W incandescent load drew 45.12A (22.56 x 2= 45.12A) at a voltage of 119.4 (see meter screen capture below.) As you can see by these tests, changing the turns ratio to increase voltage drew only 2.18 Amps more when boosting the voltage by 5%, and only 4.8 Amps when boosting the voltage by 10% - hardly enough to trip primary supply overcurrent protection as Marc suggests. And, when you compare the 42.5 and 45.12A Amps drawn by our 5000W load to the 41.94 Amps it should draw according to Ohm’s Law (W=VA or 5000W/119.2V = 41.94A), the .56 and 3.18 Amps more current drawn puts the efficiency of our Transformer/Distro at between 92.5 and 98.7% (42.5A - 41.94A = .56A, .56A/41.94A = .013 or 1.3%, 100 – 1.3 = 98.7% efficiency.) So technically, Marc is correct in that a 30A/240V dryer receptacle will NOT be able to power a full 7200VA load (30A x 240V = 7200VA) at 120V through a 240-to-120V step-down transformer – it will however be able to power only a 7106VA load (7200 x .987 = 7106.4.) If we agree not to quibble over the 93.6 VA difference (7200 – 7106 = 93.6VA), it is fair to say that our 60A Transformer/Distro gives you access to the full power available in the 240V receptacle in a single large 120V circuit that is capable of powering larger lights, or more smaller lights, than you could otherwise. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

Marc Roessler wrote: "… the transformer itself has losses. Not too much resistive loss (i.e. heat generated), but it is an inductive load (i.e. reactive current, bad power factor!) so you can't make use of all of that amperage. Depending on the transformer, this means that a 30A/240V dryer receptable will NOT be able to power a full 30*240=7200VA lamp at 120V through a 240-to-120V step-down transformer." Thus far we have assumed an ideal transformer that has no internal losses. But Marc is correct that transformers have losses. However they are not as substantial as Marc implies. A transformer does not require any moving parts to transfer energy. This means that there are no friction or windage losses associated with other electrical machines. The losses transformers do suffer are called "copper losses" and "iron losses" but generally these are quite small. Copper losses, or the resistive losses Marc refers to, is the electrical power which is lost in heat as a result of circulating the currents around the transformer’s copper windings, hence the name. Copper losses represent the greatest loss in the operation of a transformer. Iron losses, also known as hysteresis, is the lagging of the magnetic molecules within the core, in response to the alternating magnetic flux. This lagging (or out-of-phase) condition is due to the fact that it requires power to reverse magnetic molecules; they do not reverse until the flux has attained sufficient force to reverse them. Their reversal results in friction, and friction produces heat in the core which is a form of power loss. The efficiency of a transformer is reflected in this accumulative power (wattage) loss between the primary (input) and secondary (output) windings. An ideal transformer is 100% efficient because it delivers all the energy it receives. Real transformers on the other hand are not 100% efficient and at full load, the efficiency of a transformer is somewhere between 94% and 96% - which is quite good. The efficiency of a transformer like ours, operating with a constant voltage and frequency, can be as high as 98%. So, again Marc is correct in theory, but in practice the losses in a transformer are negligible. In order to demonstrate how little power is lost to transformer inefficiencies, as well as how little effect stepping up voltage by means of taps has on the current drawn by a transformer, I conducted the following test. I used one of our modified Honda EU6500is generators to power a couple of 2ks and a 1k (5000W total load) with one of our 60A Transformer/Distros with the Voltage Select upgrade. The Voltage Select upgrade allows for the switching between taps to boost the voltage output on the secondary side to compensate for line loss. As you can see in the picture of the test set-up below, I then used a Fluke 34B Power Quality Meter to measure the current on one leg of the primary supply (clamping onto one of the hot conductors) and the meter probes to measure the voltage on the secondary side (stabbing into the 60A Gang Box plugged into the Transformer/Distro.) This way the meter screen would have both the secondary voltage (on the upper left) as well as the current drawn on one leg by the primary (half the total load of the transformer primary.) For the first trial I ran the 5000W load (the two 2ks and one 1k) without any voltage boost on the Transformer/Distro and only 50’ of twist-lock extension between the generator and the Transformer/Distro. As you can see in the capture of the meter screen below, at 118.9V our 5000W incandescent load drew 40.32A (20.16A x 2= 40.32) For the second trial, I created appreciable voltage drop through line-loss by adding 300 more feet of twist-lock extension between the generator and the Transformer/Distro. Without using the “Voltage Select” capability to boost voltage to compensate for the line-loss, our 5000W incandescent load drew 38.5A (19.25A x 2= 38.5A) at a reduced voltage of 113.9V (see meter screen capture below.) For the third trial, I compensated for the appreciable voltage drop over the 350 feet of twist-lock extension between the generator and the Transformer/Distro by using the “Voltage Select” switch to boost voltage on the secondary side by 5% to compensate for the 5V line-loss. Where I have run out of space, I will pick up this post later. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

In a post recently under “Newbie. Bought 2kW Mole Super Softlite. How to power it?” thread, Marc Roessler posted that operating at 120V through a 240V-to-120V transformer/distro rather than directly into a 240V receptacle with 240V globes does not give any benefit. While Marc makes some very good points, and is even correct in theory on some, in realty things are very different. So different that I do not agree with the conclusions he draws. Where the following discussion pertains to how to access more power through 240V receptacles than it does to the original post, I have started a new thread. I would like to address his points one at a time. Marc Roessler wrote: "Yes, you can compensate for the line loss by choosing different taps at the transformer (like with the old Colortran system). But this will raise power consumption (amperage/current) on the primary 120V side. You don't save any energy. At some point your primary breaker will trip if you keep compensating by upping the secondary voltage by changing the transformer taps." If we look at the fundamental principles by which transformers operate, we see that while this is true in theory, in practice it is not a concern because the increase in current is negligible. A step-down transformer consists of two sets of coils or windings (a basic two-winding transformer is shown in the Figure below.) Each set of windings is simply an inductor. AC voltage is applied to one of the windings, called the primary winding. The other winding, called the secondary winding, is positioned in close proximity to the primary winding, but is electrically isolated from it. The alternating current that flows through the primary winding establishes a magnetic flux that induces a voltage across the secondary winding. In other words, the secondary winding converts the magnetic field generated by the primary winding into electrical power producing the required output voltage. Because the same magnetic flux links the turns of both the windings together, the same voltage is induced in each coil turn of both windings. For example, if we have a transformer with a single turn in the primary, and only one turn in the secondary. And, if one volt is applied to the one turn of the primary coil, assuming no losses, enough current will flow and enough magnetic flux will be generated to induce one volt in the single turn of the secondary. That is, each winding supports the same number of volts per turn. From this example we can see that in an ideal transformer (one with no internal losses), the power available in the secondary winding will be the same as the power in the primary winding. Transformers are then constant wattage devices that do not change the power only the voltage to current ratio. For this reason, a transformer is all about "ratios." The difference in voltage between the primary and the secondary windings is achieved by changing the number of coil turns in the primary winding ( NP ) compared to the number of coil turns on the secondary winding ( NS ). As the transformer is a linear device, a ratio now exists between the number of turns of the primary coil divided by the number of turns of the secondary coil. This ratio is called the "turns ratio" and it’s value determines the corresponding voltage available on the secondary winding. A 240V-to-120V step-down transformer has a turns ratio of 2 to 1. Given how transformers operate, to maintain a desired voltage on the secondary side in the face of a voltage drop from line-loss on the primary side requires increasing the magnetic flux generated by the primary coil. This can be accomplished by one of two means. As Marc suggests, we can substantially increase the current through the coil which may result in tripping the primary supply overcurrent protection, or we can keep the same current flowing, and instead decrease the number of coil turns of the primary winding. If each turn of the primary coil corresponds to higher voltage, when multiplied by the turns in the secondary coil, the voltage output on the secondary will be boosted. In other words, we can control the voltage output of the secondary by changing the turns ratio slightly. Since it is quite often desirable to adjust voltage output by means of the turns ratio in this fashion, without substantially increasing the current drawn, a part of the primary winding on the high voltage side of a step-down transformer is tapped out allowing for easy adjustment. The tapping is preferred on the high voltage side as the volts per turn are lower than the low voltage secondary side. Regardless of which side is tapped, controlling the voltage output of the secondary by changing the turns ratio does not appreciably increase the current in the primary coil and so is not likely to lead to tripping the primary supply overcurrent protection as Marc suggests. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

You won’t have any flicker issues with the tungsten lights. And, as long as you use Kino Flos you won’t have issues because their ballasts operate at very high frequencies (20-40kHz.) Where you might run into trouble is with the 6k Par. If you end up with a 6k with a magnetic ballast and a generator that is not governed to film specs, you will definitely have flicker problems. There are too many variables to say with certainty, so I would suggest you use this link for why HMIs flicker and how you can avoid it. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

Most Kino Flos are not power factor corrected and, as demonstrated in the oscilloscope shots below, 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 draw such harmonically distorted current 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”.) 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 harmonic noise can build to a point where it will have an adverse effect upon other equipment, such as Will’s Arri 575 HMI, 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, Fluorescent, & LED ballasts in use today. Running incandescent lights on generators was never a problem because as purely resistive loads they didn’t create harmonic currents. 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. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

The reason the cheap Chinese clones work on the grid and not on portable generators is that the ballasts are not Power Factor Corrected (PFC.) As such, they draw current in abrupt bursts that are rich in harmonics. On the high impedance of generators, the harmonic currents drawn by non-PFC ballasts can cause voltage waveform distortion that can trip the generator’s breakers. Depending on the size and design of the generator, it may have 5 to 100 times greater impedance than a power grid transformer. Consequently, harmonic generating loads which work fine on utility power, will react entirely different when powered by a generator. In practice, when you plug a HMI light into a wall outlet you need not be concerned about current harmonic distortion producing voltage distortion. The impedance of the power source (the grid) is so low, the distortion of the original applied power waveform so small (less than 3%), and the power plant generating capacity so large by comparison to the load, that harmonic currents fed back to it will not effect the voltage at the load bus (as can be seen in the left hand oscilloscope shot below. ) Left: Grid Power w/ 1.2Kw Arri non-PFC Elec. Ballast. Right: Conventional Generator Power w/ 1.2Kw Arri non-PFC Elec. Ballast. As is evident in the right hand oscilloscope shot above, it is an all together different situation when plugging a 1200W HMI into a small portable generator. Given the comparatively large sub-transient impedance of conventional AVR portable gas generators, and the high THD value of their inherent power waveform (see no load waveforms below), you have a situation where even a small amount of harmonics being fed back into the power stream will result in a large amount of harmonic distortion in its’ voltage. Left: Original Grid Waveform w/no load & low THD (>3%) Right: Original conventional AVR Generator (Honda EX5500) waveform w/ no-load & high THD (@17%) Making the matter worse is that, given the increasing prevalence of non-linear light sources, such as LEDs and Flos in production, it is likely that the percentage of the generator’s capacity taken up by non-linear loads will be very high given its small size relative to the size of HMIs typically used on these generators (575-2500 Watts.) Small portable conventional AVR generators present a perfect (electrical) storm where the return of any harmonic currents results in a very high degree of voltage distortion and tripping breakers. These power generation issues have been vexing set electricians for years. Use this link for an article that explains the electrical engineering principles behind these issues and how to resolve them. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

For the load that Busker wants to power (incandescent lights, monitor, etc.), a Coleman Powermate 2250 will work. But, if instead of incandescent lights he were to use Flos, or HMIs, it may not. Sizing a portable generator for a lighting load can be very complicated when you use lights sources like HMIs, Kinos, CLF lamp banks, & even LEDs. On generators it matters not only what type of generator you use but also what type of ballasts the lights use. The poor Power Factor and Harmonic Noise that magnetic and non-Power Factor Corrected electronic ballasts (HMI, Kino, CFL, & LED incld.) kick back into the power stream can have a severe adverse effect on the power waveform of some generators, but not others. And, as more and more powerful LED fixtures come onto to market, there is the potential hazard that, because of the low wattage of the individual fixtures, users are lulled into complicacy. If the LED fixtures are not Power Factor Corrected, then their low wattage can create a dangerous sense of false security when it comes to sizing a portable generator for LED loads consisting of large arrays (like the ones pictured below) or in quantity on portable generators. Besides the examples pictured here, take a hypothetical independent feature film shooting a night scene on a city street with a Canon DSLR. Because of the speed and light sensitivity of the camera and the amount of ambient light from store windows and street lamps they figure they can get away with a lighting package consisting of a 800W Joker Buglite to augment the background and four 40W 1x1 Litepanels to model their talent? It is a low budget production, so they can’t afford a grip truck but instead trick out a rental box. The rental box can’t tow a generator, so they plan instead to use a portable gas generator. Why not, after all they are using only energy efficient LEDs and a Joker 800? They opt for a conventional 1000W generator figuring it will be enough(800W+40W+40W+40W+40W = 960W). Will it work? No, because of the low wattage of the lights, they failed to consider their Power Factor when calculating the load that they will put on the generator and so they overload it. A careful analysis of the Power Factor of their lights (the Joker 800 and 1x1 Litepanels) indicates that their lighting package would in fact draw 1675W. Why? If we look at the technical specifications for the Joker 800 Buglite, we see that it uses a non-Power Factor Corrected ballast with a Power Factor of .58. According to the K5600 website, the Joker 800 ballast draws 12.5 Amps rather than the 7 Amps you would think using Ohm’s Law (800W/110V=7.2A.) What that means is that it has an Apparent Power of 1375W (110V x 12.5A = 1375W) or draws nearly twice the power to generate 800W of light output than a quartz instrument of the same wattage. Used on wall outlets, this relatively inefficient use of power is negligible because the power draw of the Joker 800 fits easily in a standard wall circuit. However, the greater Apparent Power of the Joker 800 must be factored when using portable generators because the generator must be sized to supply the Apparent Power (1375W), even though only the True Power (800W) provides light. The same is true when it comes to the 1x1 Litepanels. According to the manufacturer, the AC-to-DC power supply that Litepanel uses for their 1x1 fixtures has a Power Factor of .54 and so draws nearly twice the power (an Apparent Power of 75W) for it’s true power output of 40W. If you were to use this lighting package on a 1000W conventional generator, the total Apparent Power of 1675W (1375W + 75W + 75W 75W + 75W = 1675W), would overload the generator. Even though it’s power is cleaner and more stable, you would not be able to run this package on a Honda EU1000is Inverter Generator either because, with a continuous load rating of 900W, the accumulative load of 1675W would also overload a 1000W inverter generator. Could you operate this lighting package on a conventional generator like the Coleman Powermate 2250 mentioned above? Again, the answer is “no” because the greater Apparent Power of lights with a poor Power Factor is not the only consideration when operating them on conventional generators. Of equal importance, is the Harmonic Noise that ballasts with poor Power Factor kick back into the power stream that severely limits the total amount of Leading Power Factor loads, as compared to Unity Power Factor loads, that can be reliably operated on conventional generators. Left: Grid Power w/ 1.2Kw Arri non-PFC Elec. Ballast. Center: Conventional AVR Power w/ 1.2Kw Arri non-PFC Elec. Ballast. Right: Inverter Power w/ 1.2Kw Arri non-PFC Elec. Given the large sub-transient impedance of conventional generators even a small degree of harmonic noise being fed back into the power stream will result in a large amount of distortion in its’ voltage (see oscilloscope shots above.) Add to that, the fact that the original supply voltage waveform of conventional generators is appreciably distorted to begin with, and you have a situation where the return of any harmonic currents by a non-PFC HMI, Fluorescent, or LED ballast will result in significant waveform distortion of the voltage at the power bus and operational problems with the generator voltage and frequency regulation. This is graphically illustrated in the You-Tube video, “Compact Fluorescent verses The Generator", by Lighting Designer Kevan Shaw’s (available on-line at http://www.youtube.com/watch?v=LeCqreRMzKM), when he is not able to operate an equivalent Apparent Power of CFLs, as he could incandescent light, on his small 850W generator. For the same reason that Kevan Shaw was not able to operate more than 270 Watts of CFL bulbs (15–18W bulbs) on his little 850W generator, our hypothetical indie feature will not be able to operate their lighting package on a 2000W conventional AVR generator like the Coleman Powermate 2250 mentioned above. After all CFLs have the same Power Factor as the Litepanel 1x1 power supplies (.54.) The adverse effects of the harmonic currents that non-PFC ballasts generate, so graphically demonstrated in Kevan’s video, limits the total amount of Leading Power Factor loads, as compared to Unity Power Factor loads, that can be reliably operated on conventional AVR generators. In fact, Kevan Shaw’s You-Tube video illustrates the old math that it is not possible to load conventional generators beyond roughly 65% of their rated capacity for more than a short period when the load consists of lights with a poor Leading Power Factor (Max Apparent Power of 540W/850W Generator = .64) Which translates to a maximum load of 1300W on a 2000W conventional generator. Where the total Apparent Power of our lighting package consisting of a Joker 800 and a couple of 40W 1x1 Litepanels is 1525W, it will overload even a 2000W conventional generator. Will our lighting package operate on a 2000W inverter generator like the Honda EU2000is? The oscilloscope shots above indicate that it would. Even though the non-PFC ballasts of our lighting package kick back the same harmonic currents, the voltage waveform of inverter generators retain an over all sinusoidal shape because of their lower system impedance and purer original power waveform. The appreciable difference in voltage distortion created here by the same light demonstrates that an inverter generator will provide cleaner power, and operate more reliably, regardless of the type of load. Left: Grid Power w/ 1.2Kw P-2-L PFC Elec. Ballast. Center: Conventional AVR Power w/ 1.2Kw P-2-L PFC Elec. Ballast. Right: Inverter Power w/ 1.2Kw P-2-L PFC Elec. Ballast As the oscilloscope shots above illustrate, Power Factor Correction can be of tremendous benefit when operating HMIs, Kinos, and LEDs on portable gas generators because a PFC circuit realigns voltage and current, eliminates the generation of harmonic currents, and induces a smoother power waveform at the distribution bus. PFC circuits successfully increase the power factor to as much as .98, making ballasts with it near linear loads. As a result, the ballast uses power more efficiently with minimized return current and line noise and also reduces heat, thereby increasing their reliability. For instance, if you were to replace the Joker Ballast with a Power-2-Light 800W PFC HMI ballast instead, the same head would draw 8 Amps at 110 Volts (instead of 12.5) and have an Apparent Power of only 880 Watts. If you were also able to replace the non-PFC AC power supplies of the 1x1 Litepanels with Power Factor Corrected ones, the oscilloscope shots above also indicate that you would likely be able to operate the whole package on a 1000W inverter generator (880W + 40W + 40W = 960W.) What is true of small lighting loads on small generators is also true of larger lighting loads on larger generators. For instance, before reading this post, you would have thought that you could reliably operate a 4k HMI with non-PFC ballast on a conventional 6500W generator. But, where a non-PFC 4k electronic ballast will draw 58A at 120V it will overload a 6500W. To understand why, simply compare its’ Apparent Power of 6960W (58A x 120V = 6960W), to the continuous load capacity of a conventional 6500W generator after de-rating it for a load with Leading Power Factor of .58 (6500W x .65 = 4225W.) Likewise, if you were to replace the non-PFC 4k electronic ballast with a Power Factor Corrected one, the light would only draw 38A at 120V and have an Apparent Power of 4560W. And since, the ballast has a near Unity Power Factor, the 6500W generator would not have to be de-rated, and so could operate the 4560W Apparent Power load without a problem. These power generation issues have been vexing set electricians for years. Use this link for an article that explains the electrical engineering principles behind these issues and how to resolve them. Even though the poor Power Factor of an individual Litepanel will not have a disastrous effect on a portable generator, poor Power Factor should be eliminated wherever possible because its’ accumulative effect can be severe. Where just about every piece of production equipment used on set today (including video cameras, field monitors, hard-drives, lap-tops, and battery chargers) generates harmonics a viscous cycle can get started with unpredictable results like those evidenced in Kevan Shaws You-tube video. Guy Holt, Gaffer, ScreenLight & Grip, Lightng Rental & Sales in Boston

I have included a table that correlates CC (Color Compensating) values and Color Correction Gel in a white paper that explains why the use of the available color correction gels to correct LEDs is a misapplication of a finely calibrated system of correction designed for continuous spectrum light sources only. Test results also included in the white paper clearly demonstrate that their use yields unexpected and undesirable results when applied to LEDs. Use this link for details and the table. Guy Holt, Gaffer, ScreenLight and Grip. Lighting Rental & Sales in Boston

Where are you located? Guy Holt

I also don’t recommend that you try to power lights with an inverter through the lighter socket. Car lighter sockets are only capable of handling a couple of hundred Watts at most. To run this load you would be better off, as Zac suggested, with a "Battverter" - which is a Battery/Inverter system. A "Battverter" system consists of a 12V DC power source (usually Marine Cells), a DC-to–AC True Sine Wave Power Inverter, and a Battery Charger. Wire these components into a Road Case or milk crate and you can put it on the floor in the back of the car. Here are some production stills that show you two Battverter systems I built to run lights in vehicles at various times. The first is a 750W "Battverter" rig wired into in Calzone case. To maximize the running time on the batteries, I made up a "jumper cable" that we attached to the leads of the pickup truck's battery. That way the engine alternator charged the batteries as they were being discharged by the light. Tie–ing the Battverter into a vehicle engine will extend the running time on your Battverter batteries so much that they may never run out of power. The production stills below show a more elaborate 1800W Battverter system that we built to run 16 - 4’ kinos tubes inside the airport shuttle bus. Use this link for details on how we wired it into the shuttle bus. (Kino Flo 4x4s rigged to an exo-skeletal frame of a Shuttle Bus and powered by an 1800W Battverter) If you don’t require a lot of light, a Battverter will even enable you to use a car engine as a generator. Use the engine to run the lights through the Battverter as described above during set up and rehearsals. When it comes time to shoot a take, simply shut off the engine and continue to run the lights on the Battverter alone. Running the vehicle engine between takes charges the batteries so that they will run lights all night. (Custom 1800W BattVerter powers 16 - 4' Kino Flo single tubes rigged in the interior and on the exterior of an Airport Shuttle) When building these rigs, keep in mind that when voltage goes down, amperage goes up. Wire that carries 12V DC has to be much larger than that which carries the same load at 120V AC. For instance to supply 12 volts to the 1800W inverter used on the shuttle bus required that we run 2 ought feeder to the buses' alternator. Also be sure that the alternator is large enough to take the load without burning out. Finally, You have to be really careful when choosing a DC-to-AC inverter for film production because there are three basic types of inverters and not all of them are suitable for all types of motion picture lights. For more information on what type of inverters to use with different type of lights I would suggest you read an article I wrote about portable generators that is available online at http://www.screenlightandgrip.com/html/emailnewsletter_generators.html. Since inverter generators use the same three types of inverters, the information in the article is applicable to stand alone DC-to-AC inverters designed for use with batteries as well. Guy Holt, Gaffer, SceenLight & Grip, Lighting and Grip Rental & Sales in Boston.

You could outfit one yourself with a Bates, or we rent/sell them already outfitted with Bates and Voltage Select Switches. Contact me off forum for details. Another option that has occurred to me is that, since a 2k Super Soft consists of two 1kw globes on separate switches, you could split the two globes onto separate circuits with separate plug ends. That way you are only plugging a 1kw into each wall circuit. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

The Quick 220 Power Supply is not as straight forward as it appears: the two outlets it uses to make 240V must be on different circuits that are out of phase (opposing legs of the electrical service) and not controlled by ground fault interrupters (GFI's). And, if the service is 3 Phase rather than Single Phase, you will get 208V without any means of stepping it up to 240V. At 208V a 240V bulb will look quite dim and very warm. There are a couple of good reasons why you may still want to operate a 2k at 120V through a transformer/distro rather than directly into a 240V receptacle. First, a 30A/240V dryer receptacle offers you 60A at 120V through a 240-to-120V step-down transformer. If you plug the 2k in through a transformer/distro and operate it at 120 Volts you still have 43.2 Amps left over to power additional lights through the transformer as well if your. That’s a lot of power in an easily distributed form to not take advantage of. Master shot of an iRobot commercial lit with a 4kw HMI Par (outside) & 1.8kw HMI Par (inside) powered from a 30A/240V dryer outlet through a step-down transformer/distro. Note: Sunny feel created by 4k Par on an overcast day. The second reason is that if the 2k is far from the 240V receptacle you can have appreciable line-loss (voltage drop) over a long cable run. A transformer/distro can be used to compensate for line loss, as well as the voltage drop on a generator from running it near full load. Our transformer/distros provide variable taps on the primary side that enable you to adjust the step down ratio to boost their output above the standard 2:1 ratio. This boost capacity will compensate for accumulative voltage drop and assure full line level (120V) on set. Left: Transformer/Distro plugged into a 30A/240V dryer outlet. Right: 4K HMI Par under rain protection powered by Transformer/Distro This feature of our transformer/distros was a real benefit on a recent commercial for iRobot (see production stills attached.) The spot contrasted the iRobot Scooba designed to clean kitchen floors to the old mop and bucket approach. For the mop and bucket approach we had a haggard looking Mom slopping water all over the kitchen floor as kids ran slipping and sliding across the floor. Left: Arri AS18 1800W Par powered from Transformer/Distro. Right: 4Kw and 1800W HMI ballasts powered from Transformer/Distro. The only available source of power for our 4K and 1800W HMIs was a dryer receptacle in the laundry room. Unfortunately, the laundry room was upstairs and in the front of the house and the kitchen was downstairs and in the back. Fortunately, we could use the boost capacity of our transformer/distro to compensate for the 16.5V line loss we experienced after running 300’ of high voltage twist-lock extension from the front to the back of the house. You wouldn’t think there would be that much voltage-drop over a 300’ 10AWG cable run, except that in this case, the electrical service was in the basement under the kitchen where we were shooting. Which means the circuit supplying our lights consisted of approximately 300’ of wire from the electrical panel in the basement under the kitchen to the dryer receptacle upstairs in the front of the house, plus the 300’ of wire we ran back to the kitchen, for a total of approximately 600’ (see voltage drop table below.) Note: the voltage drop on a 600’ run of 10AWG stranded cable is 16.497 volts An added benefit to using a transformer/distro in this case was that it enabled us to use a 100A Shock Block to offer GFCI protection for cast and crew. We knew water would get everywhere inside the kitchen, so to protect the cast we put a 100A Shock Block like the one pictured below on the load side of the transformer/distro to provide Ground Fault protection inside around the wet kitchen floor. It was a good thing that we did, because it ended up pouring rain that day and so the Shock Block did double duty for the 4k that was outside the kitchen window. A single 100A GFCI "Shock Block" can provide ground fault protection on wet locations for the entire distro system of a Honda 6500 portable generator when used in-line with a Step-Down Transformer/Distro. I regularly use transformers to power not only big HMIs (2.5-4Kw), but also quartz 5ks, in situations where a tie-in is not an option and the budget doesn’t permit for a tow generator. Use this link for more details about using step-down transformers on set. By giving you safe and legal plug-in access to more house power through common 240V house outlets, a transformer can quite often eliminate the need for tie-ins or generators. Guy Holt, Gaffer, ScreenLight & Grip, Lighting rental and sales in Boston

Using a 240v-to-120v step-down transformer is without a doubt the most reliable way to power a 2k on wall out-lets. A transformer will convert the 240V output into a single large 120V circuit that is more than capable of powering the 16.8A load of a 2k at 120V. If you outfit the transformer with a 60A Bates receptacle, it will enable you to use a real film style distro system that will minimize line loss over a long cable run, and provide a 20A circuit right at the light. Common 240V sources found on interior locations include Range Plugs, Dryer Plugs, and special receptacles installed for Window Air Conditioners. While you can put a 15A Edison Plug on a 2k, as Adrian suggests, you still have to find a 20A circuit – which is not always conveniently located. You definitely want to avoid long runs of stingers because the odds are good that there will be an old and weak plug end somewhere in the run that will overheat and melt since they too are only rated for 15 Amps. And, it has been my experience that 2ks with 15A Edison Plugs get really hot and eventually melt because the stranded copper in the plug becomes brittle and breakdowns from the heat over time. 2ks, like 1800W HMIs, are in the class of lights that work best on a real film distribution system where every circuit is 20 Amps, you know what is on the circuit because you are loading it yourself, and you are bringing the receptacle to the light because you are distributing the power yourself. When you can run a 60A whip and drop a Snack Box with a 20A outlet next to the light you won’t have a problem. But, if your style of shooting requires that you run multiple stingers to plug into a wall or generator outlet, you will likely have problems with the plug ends or receptacle overheating and causing the breaker to overheat and trip. A step-down transformer will enable you to use real film distro and avoid these problems without having to do a dangerous tie-in or rent an expensive generator. Use this link for more detailed information on successfully operating large tungsten lights on wall outlets. If Austin doesn’t need all of the output of a 2k soft, another option is to swap the 1k FCM bulbs for 750W EJG bulbs. Now a 1500W softlight, the head will draw only 12.6 Amps at 120V and fit comfortably on the common 15A circuit and not overtax Edison plugs and outlets. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Sales & Rentals in Boston

The trick to lighting the haze so there is an omnipresent light source (being the haze), is to use a very even diffuse source. Blondes strung over-head or on scaffold towers would probably be too sourcie (sp?) to work. How Shelly Johnson was able to separate the layers of trees and characters by lighting haze was, as David posted, to use large lights far down an embankment and diffuse them heavily so that they would spread evenly before reaching the action area. The 6' Color Kinetics ColorBlaze 72 RGB LED A low budget approach that would accomplish the same thing without a steep embankment or large HMIs would be to use a ground row of Color Kinetic ColorBlaze 72 LED fixtures. Each fixture is 6 feet long and can be strung end-to-end to cover a long distance. If you use the newer dmx four channel RGBA fixture, you will be able to dial in with a dimmer board the color blue you want without losing output to color gels as you would with your quartz blondes. And with a maximum draw of 420 Watts at full output you can operate up to 15 of them (enough to cover 120 linear feet) on a 7500W modified Honda EU6500is - which will save you having to run feeder cables through the woods (there is nothing worst than running cable through woods at night.) In fact, you could probably light your entire night scene with nothing more than a couple of 7500W Honda EU6500is portables just as the makers of “Gasp” did (pictures attached). But, beware, their power factor deteriorates as they are dimmed or only single color emitters are used. Which means that they will draw current rich in harmonic distortion, which will have severe adverse effects on most portable generators. The harmonics generated by these lights, and any other non-Power Factor Corrected sources (HMIs, KINOs, LEDS) you might use, can cause severe voltage waveform distortion and higher than normal return current on the main neutral conductor which can result in it overheating and catching fire. Night exterior beach campfire scene lit with only a 7500W modified Honda EU6500is portable generator For this reason, I would not operate them on conventional AVR putt-putts through splitter boxes, but only through an inverter generator (like the Honda EU6500is) and a transformer/distro with super neutrals (use this link for details.) Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental and Sales in Boston

It gets a bit more complicated with HMIs because it not only matters what type of HMI ballast you use, but also what type of generator you use. If the OP were using incandescent lights, he could use a AVR type generator (AVR stands for Automatic Voltage Regulator.) However, the harmonic noise that a non-Power Factor Corrected (PFC) electronic HMI ballast will kick back into the power stream can have a severe adverse effect on the power waveform of conventional AVR generators like the Honda EX5500 (the “older EX 5.5 Silver” one Leonardo mentioned.) The harmonic noise these light sources generate will not have nearly as bad an effect on the power supplied by an inverter generator like the Honda EU6500is. As the middle oscilloscope shot below indicates, when you power a standard non-PFC HMI Electronic ballast from a conventional portable generator, the harmonic noise they kick back into the power stream can have a severe adverse effect on the power waveform. Given the large sub-transient impedance of conventional portable generators, even a small degree of harmonic noise being fed back into the power stream will result in a large amount of distortion in its’ voltage. Left: Grid Power w/ 1.2Kw Arri non-PFC Elec. Ballast. Center: Conventional AVR Power w/ 1.2Kw Arri non-PFC Elec. Ballast. Right: Inverter Power w/ 1.2Kw Arri non-PFC Elec. Ballast. The adverse effects of the harmonic noise exhibited here, can take the form of overheating and failing equipment, circuit breaker trips, excessive current on the neutral wire, and instability of the generator’s voltage and frequency. Harmonic noise of this magnitude can also damage HD digital cinema production equipment, create ground loops, and possibly create radio frequency (RF) interference. When your lighting package consists predominantly of non-linear light sources, like HMI, Fluorescent, & LED lights, it is essential to have Power Factor Correction circuitry (PFC) in the ballasts and to operate them on an inverter generator. The combination of improved power factor and the nearly pure power waveform (1-2 %THD) of a inverter generator creates clean stable set power (like that in the power waveform below right). Left: Grid Power w/ 1.2Kw P-2-L PFC Elec. Ballast. Center: Conventional AVR Power w/ 1.2Kw P-2-L PFC Elec. Ballast. Right: Inverter Power w/ 1.2Kw P-2-L PFC Elec. Ballast. Chris’s best bet would be to use a 1.2kw HMI with PFC ballast and use an inverter generator like the Honda EU6500is. The Honda EU6500is will also generate less than half the noise of an AVR type generator – making it easier to record clean audio tracks. For more details on what type of generator to use with HMIs and fluorescent lights read the article I wrote for our company news letter on the use of portable generators in motion picture production. The article is available online at http://www.screenlightandgrip. com/html/emailnewsletter_generators.html. Guy Holt, Gaffer, ScreenLight & Grip, Lightng & Grip Rental and Sales in Boston

You may want to consider using a combination of hard and soft light to create contrast in a situation where the overhead fluorescent lighting is usually very flat as we did in a short film called "Act Your Age" that takes place in a senior center (see the production stills attached.) However to hang anything larger than a 650 or to hang kino banks you will need something like the hangers pictured below: One of the biggest challenges in situations like this is getting light into the eyes of your talent. If you don't, your talent's eye will look dark and bruised because the very toppy light of the overhead fluorescents won't dig into their eyes. You may want to consider the approach we took in the production stills above, where we hung 4'-4 Bank kinos with Opal coved below the fixture to make a "Bay Light." Coving the Opal under the light, redirects it horizontally so that it will dig into the talents eyes. As you can see here, with the right rigging equipment, you can use drop ceilings like a studio grid. Use this link for more pictures of productions that used drop ceilings on location as if they were a studio grid. You can run a 2.5 HMI off of common wall outlets. Most offices have a 240V receptacle of some kind. Common 240V circuits in offices include, Copier receptacles, range receptacles, and special receptacles installed for coffee makers. The latest generation of 2.5/4k HMI ballasts will operate on either 120V or 208-240V and fit comfortably in these circuits. If you are using an older ballast that runs only on 120V, you can step-down a 240V circuit to 120V with a transformer. A step down transformer will convert the 240 volts supplied by 240V receptacles to 120 volts in a single circuit that is the sum of the two single-phase legs of 30/50 amps each (60A usually). Now that you have a larger 120V circuit, you can operate larger lights like 2.5 or even 4k HMIs, or more smaller lights, than you could otherwise. A step-down transformer can do the same with the enhanced 7500W/240V output of a Honda EU6500is Generator. By giving you access to more "house power" through common 240V household outlets, a Transformer/Distro can eliminate the need for dangerous tie-ins or expensive tow generators (use this linik for details.) Guy Holt, Gaffer, ScreenLight & Grip, Lightng & Grip Rental in Boston

There are a couple of good reasons why you may still want to operate a 2.5kw HMI at 120V through a transformer/distro rather than directly into a 240V receptacle. First, a 30A/240V dryer receptacle offers you 60A at 120V through a 240-to-120V step-down transformer. If you plug the 2.5kw HMI in through a transformer/distro and operate it at 120 Volts you still have 37 Amps left over to power additional lights through the transformer as well if your 2.5kw ballast has Power Factor Correction. That’s a lot of power in an easily distributed form to not take advantage of. Master shot of an iRobot commercial lit with a 4kw HMI Par (outside) & 1.8kw HMI Par (inside) powered from a 30A/240V dryer outlet through a step-down transformer/distro. Note: Sunny feel created by 4k Par on an overcast day. The second reason is that if the 2.5kw HMI is far from the 240V receptacle you can have appreciable line-loss (voltage drop) over a long cable run. A transformer/distro can be used to compensate for line loss, as well as the voltage drop on a generator from running it near full load. Our transformer/distros provide variable taps on the primary side that enable you to adjust the step down ratio to boost their output above the standard 2:1 ratio. This boost capacity will compensate for accumulative voltage drop and assure full line level (120V) on set. Left: Transformer/Distro plugged into a 30A/240V dryer outlet. Right: 4K HMI Par under rain protection powered by Transformer/Distro This feature of our transformer/distros was a real benefit on a recent commercial for iRobot (see production stills attached.) The spot contrasted the iRobot Scooba designed to clean kitchen floors to the old mop and bucket approach. For the mop and bucket approach we had a haggard looking Mom slopping water all over the kitchen floor as kids ran slipping and sliding across the floor. Left: Arri AS18 1800W Par powered from Transformer/Distro. Right: 4Kw and 1800W HMI ballasts powered from Transformer/Distro. The only available source of power for our 4K and 1800W HMIs was a dryer receptacle in the laundry room. Unfortunately, the laundry room was upstairs and in the front of the house and the kitchen was downstairs and in the back. Fortunately, we could use the boost capacity of our transformer/distro to compensate for the 16.5V line loss we experienced after running 300’ of high voltage twist-lock extension from the front to the back of the house. You wouldn’t think there would be that much voltage-drop over a 300’ 10AWG cable run, except that in this case, the electrical service was in the basement under the kitchen where we were shooting. Which means the circuit supplying our lights consisted of approximately 300’ of wire from the electrical panel in the basement under the kitchen to the dryer receptacle upstairs in the front of the house, plus the 300’ of wire we ran back to the kitchen, for a total of approximately 600’ (see voltage drop table below.) Note: the voltage drop on a 600’ run of 10AWG stranded cable is 16.497 volts An added benefit to using a transformer/distro in this case was that it enabled us to use a 100A Shock Block to offer GFCI protection for cast and crew. We knew water would get everywhere inside the kitchen, so to protect the cast we put a 100A Shock Block like the one pictured below on the load side of the transformer/distro to provide Ground Fault protection inside around the wet kitchen floor. It was a good thing that we did, because it ended up pouring rain that day and so the Shock Block did double duty for the 4k that was outside the kitchen window. A single 100A GFCI "Shock Block" can provide ground fault protection on wet locations for the entire distro system of a Honda 6500 portable generator when used in-line with a Step-Down Transformer/Distro. I regularly use transformers to power not only big HMIs (2.5-4Kw), but also quartz 5ks, in situations where a tie-in is not an option and the budget doesn’t permit for a tow generator. Use this link for more details about using step-down transformers on set. By giving you safe and legal plug-in access to more house power through common 240V house outlets, a transformer can quite often eliminate the need for tie-ins or generators. Guy Holt, Gaffer, ScreenLight & Grip, Lighting rental and sales in Boston

HMI Balloon Lights usually come in 4k sizes. The smaller wattage and the fact that they are a much more diffuse omni-directional source means they have considerably less output than a 9kw M90 that uses a polished reflector to focus the light output of the globe in one direction. Check with your local rental house for rental rates for the Arri M90 and Honda EB10000 generator. Guy Holt, Gaffer, ScreenLight & Grip, Lighting Rental & Sales in Boston

There are several ways of rigging lights onto or under the basket of a condor depending on the light and application. The preferred means of rigging onto the basket is to use the condor bracket below. There have been several developments in the use of aerial lifts recently that you should be aware of. The first is that the lift manufacturers are finally supporting their use in motion picture production. The upside to this development is that they now provide them painted black (see picture below) and they have endorsed the rigging of lights on their baskets, which is a good thing except that in doing so the manufacturers have set strict weight restrictions that vary depending on the height and reach of the basket and how far off the basket pivot point the light is rigged (see representative illustration below.) When rigging lights with a condor bracket on the front rail of a condor basket (as pictured above), the endorsements are in fact so restrictive that electric trailers now carry shipping scales to weigh the equipment and only the smallest guys on a crew qualify for “condor duty.” Quite often the lifts have to be sent up unmanned, and the lights focused from the ground by panning and tilting the basket with the ground controls because there is not sufficient capacity in the basket for an operator. For this reason, Arri has incorporated their new MAX reflector technology into a new power class of HMI light: the M90. (The light generated by the CAD designed Max Reflector of the new M90/60 is incredibly bright and sharp.) Utilizing a new 9 kW HMI lamp, the unique MAX reflector of the M90 creates diverging parallel rays to produce a crisp light with even distribution through a wide spot/flood range. The result is a lens-less open face fixture with a quality of light close to that of a Fresnel. The elimination of spread lenses like those used on HMI Pars, makes the ARRI MAX reflector lamp heads comparable to par configurations of even a higher wattage. In fact, the M90 is brighter than some 18K Fresnels on the market, yet weighs 67lbs less. Weighing only 87lbs, verses the 154lbs of a their 18k Fresnel, two M90s can be rigged into a condor basket and operated by a technician where only one 18k Fresnel could before. (The Active Line Filtration (ALF) of the new ARRI EB 6000/9000 ballast makes it an incredibly efficient and clean load.) To power the new M90 head, ARRI has engineered a dual wattage ballast. The EB 6000/9000 will operate either the traditional 6kw SE globe in the M90 head, or the new 9kw SE globe, on supply voltages ranging from 195-250V. With Active Line Filtration (ARRI's system of Power Factor Correction) built in, the EB 6000/9000 ballast is incredibly efficient and generates virtually no harmonic noise - enabling it to reliably operate on portable gas generators like Honda's new Digital AVR 10kw EB10000 (pictured below.) Not only does the MAX reflector of this head provide more output, but it is also incredibly versatile. When you don't need the punch of a 18kw Fresnel, you can swap the 9kw globe for a 6kw globe making more power available to run additional lights on an EB10000. For example, you save 27 Amps when you swap out a 9kw bulb for a 6kw bulb. The 27 Amps you save by burning the smaller 6kw globe will power quite a few more lights when you consider that both the ARRI L7 LED Fresnel and Kino Flo Parabeam 400 use approximately 2 Amps. In fact, such versatility now enables the operation on a portable generator, like Honda’s new EB10000, of just about all the lights needed to shoot a night exterior on a digital cinema camera. This combination of smaller, brighter, more efficient lights, with more sensitive digital cameras, and new more powerful portable generators makes it now possible to achieve remarkable results on a tight budget. (Our modified Honda EB10000 with Voltage Select 84A Transformer/Distro and 14 Gallon Fuel Caddy.) One of the biggest hurdles to obtaining good production values in low budget digital cinema productions is the high cost of the blimped studio generators required to power large HMIs. Not only are blimped generators expensive to rent, but they also come with hidden costs. Since rental trucks like those from Ryder or Penske are not equipped to tow, you quite often have to hire the rental house's grip truck to tow them. And, since most rental houses require that one of their employees drive their trucks (for insurance reasons), the production has to hire a driver at roughly $575/10hrs - which is probably more than anyone else on a typical indie crew is getting paid. All of this makes the use of an 18k Fresnel in a condor very expensive. Powering a M90 with a Honda EB10000 will not only save Sean a lot of money but also save him from having to run out 400ft of feeder cable over rough terrain. Guy Holt, Gaffer, Lighting and Grip Equipment Rental & Sales in Boston Like This Quote MultiQuote

There are several ways of rigging lights onto or under the basket of a condor depending on the light and application. The preferred means of rigging onto the basket is to use the condor bracket below. There have been several developments in the use of aerial lifts since this thread ended that you should be aware of. The first is that the lift manufacturers are finally supporting their use in motion picture production. The upside to this development is that they now provide them painted black (see picture below) and they have endorsed the rigging of lights on their baskets, which is a good thing except that in doing so the manufacturers have set strict weight restrictions that vary depending on the height and reach of the basket and how far off the basket pivot point the light is rigged (see representative illustration below.) When rigging lights with a condor bracket on the front rail of a condor basket (as pictured above), the endorsements are in fact so restrictive that electric trailers now carry shipping scales to weigh the equipment and only the smallest guys on a crew qualify for “condor duty.” Quite often the lifts have to be sent up unmanned, and the lights focused from the ground by panning and tilting the basket with the ground controls because there is not sufficient capacity in the basket for an operator. For this reason, Arri has incorporated their new MAX reflector technology into a new power class of HMI light: the M90. (The light generated by the CAD designed Max Reflector of the new M90/60 is incredibly bright and sharp.) Utilizing a new 9 kW HMI lamp, the unique MAX reflector of the M90 creates diverging parallel rays to produce a crisp light with even distribution through a wide spot/flood range. The result is a lens-less open face fixture with a quality of light close to that of a Fresnel. The elimination of spread lenses like those used on HMI Pars, makes the ARRI MAX reflector lamp heads comparable to par configurations of even a higher wattage. In fact, the M90 is brighter than some 18K Fresnels on the market, yet weighs 67lbs less. Weighing only 87lbs, verses the 154lbs of a their 18k Fresnel, two M90s can be rigged into a condor basket and operated by a technician where only one 18k Fresnel could before. (The Active Line Filtration (ALF) of the new ARRI EB 6000/9000 ballast makes it an incredibly efficient and clean load.) To power the new M90 head, ARRI has engineered a dual wattage ballast. The EB 6000/9000 will operate either the traditional 6kw SE globe in the M90 head, or the new 9kw SE globe, on supply voltages ranging from 195-250V. With Active Line Filtration (ARRI's system of Power Factor Correction) built in, the EB 6000/9000 ballast is incredibly efficient and generates virtually no harmonic noise - enabling it to reliably operate on portable gas generators like Honda's new Digital AVR 10kw EB10000 (pictured below.) Not only does the MAX reflector of this head provide more output, but it is also incredibly versatile. When you don't need the punch of a 18kw Fresnel, you can swap the 9kw globe for a 6kw globe making more power available to run additional lights on an EB10000. For example, you save 27 Amps when you swap out a 9kw bulb for a 6kw bulb. The 27 Amps you save by burning the smaller 6kw globe will power quite a few more lights when you consider that both the ARRI L7 LED Fresnel and Kino Flo Parabeam 400 use approximately 2 Amps. In fact, such versatility now enables the operation on a portable generator, like Honda’s new EB10000, of just about all the lights needed to shoot a night exterior on a digital cinema camera. This combination of smaller, brighter, more efficient lights, with more sensitive digital cameras, and new more powerful portable generators makes it now possible to achieve remarkable results on a tight budget. (Our modified Honda EB10000 with Voltage Select 84A Transformer/Distro and 14 Gallon Fuel Caddy.) One of the biggest hurdles to obtaining good production values in low budget digital cinema productions is the high cost of the blimped studio generators required to power large HMIs. Not only are blimped generators expensive to rent, but they also come with hidden costs. Since rental trucks like those from Ryder or Penske are not equipped to tow, you quite often have to hire the rental house's grip truck to tow them. And, since most rental houses require that one of their employees drive their trucks (for insurance reasons), the production has to hire a driver at roughly $575/10hrs - which is probably more than anyone else on a typical indie crew is getting paid. All of this makes the use of an 18k Fresnel in a condor very expensive. Powering a M90 with a Honda EB10000 will not only save Sean a lot of money but also save him from having to run out 400ft of feeder cable over rough terrain. Guy Holt, Gaffer, Lighting and Grip Equipment Rental & Sales in Boston

If it is a long scene, you won’t be able to do it with natural light. The problem with shooting at dawn or dusk is that both the light level and color temperature changes so rapidly that when you get back to your edit suite you find that the shots don’t match. It is better to shoot mid-day, control the natural daylight, and use HMIs to create a sunset effect, than limit yourself to a brief window of opportunity at dawn or dusk. The first step to artificially creating a sunset effect is to take the direction out of the natural daylight by flying a silk out the window, and then bring in your own consistent lighting. But remember, light quality is as important as color temperature when it comes to simulating natural daylight in an interior. There are two components to daylight: hard direct sun and soft diffuse sky-shine. Because direct sunlight is a very hard source that creates crisp shadows, the traditional approach is to use a large HMI Fresnel like an 18K to simulate direct sunlight. Unfortunately, this is also a very expensive approach because it requires a movie blimped generator. One of the biggest hurdles to obtaining good production values in low budget digital cinema productions is the high cost of blimped studio generators. Not only are blimped generators expensive to rent, but they also come with hidden costs. Since rental trucks like those from Ryder or Penske are not equipped to tow, you quite often have to hire the rental house's grip truck to tow them. And, since most rental houses require that one of their employees drive their trucks (for insurance reasons), the production has to hire a driver at roughly $575/10hrs - which is probably more than anyone else on a typical indie crew is getting paid. All of this makes the use of an 18k Fresnel to simulate direct sunlight very expensive. (The light generated by the CAD designed Max Reflector of the new M90/60 is incredibly bright and sharp.) If you are shooting on a low budget, a less expensive alternative is to use the new ARRI M90 with MAX reflector. The ARRI M90 introduces a new power class for daylight fixtures. Utilizing a 9 kW lamp, developed by Osram according to ARRI's specification, the M90/60 can be operated on portable gas generators, like Honda's new 10kw EB10000, to achieve remarkable results. 
The unique MAX reflector of the M90 creates diverging parallel rays to produce a crisp light with even distribution through a wide spot/flood range. The result is a lens-less open face fixture with a quality of light close to that of a Fresnel. The elimination of spread lenses like those used on HMI Pars, makes the ARRI MAX reflector lamp heads comparable to par configurations of even a higher wattage. In fact, the M90 is brighter than some 18K Fresnels on the market. (The Active Line Filtration (ALF) of the new ARRI EB 6000/9000 ballast makes it an incredibly efficient and clean load.) Since hard direct sunlight can be unflattering as a key light for talent, and to replicate the softer more diffuse sky-shine that should also come through a window, I would suggest you use for the talent’s key source a smaller HMI, like a 2500W HMI Par, through a diffusion frame from the same general direction as the window. Diffusing the 2500 will take the “source-i-ness” out of it and placing it close to the window will enable it to spread inside the room the way natural sky-shine does. Since you can operate a 2500W HMI on common 240V wall outlets with a Transformer/Distro, and an M90 can operate on our modified Honda EB10000 generator, feature production values just became a lot more affordable for low budget digital productions. A final touch would be to fly a branch-o-loris just outside the window to create a little leaf break-up on the interior set. This would have the effect of creating some contrast (light & shadow.) I have used this same combination of 240V wall outlets and portable Honda generators to eliminate the need for tie-ins or a tow genny on many of the historical documentaries I have gaffed. For example, I have used a similar package repeatedly at a historical mansion in Easton MA called the Ames Estate. (Scene from "Unsolved History" powered from 50A/240V range outlet through step-down transformer/distro at the Ames Estate) A popular state fee free location, the Ames Estate, like many historical house/museums, does not permit tie-ins and the electrical wiring in the house is so antiquated that it is unusable. Fortunately, they have a 50A/240 volt circuit in the carriage house for a welder they use to repair the mowers they use at the park. Our standard mode of operation when shooting there is to run 250V extension cable from the welding receptacle to a 60A Full Power Transformer/Distro placed in the entry hall of the house. Using a 60A Siamese at the Transformer/Distro, we then run 60A 6/3 Bates extensions, down to the library, to the second floor, and back to the maid’s pantry. At the end of each run we put another 60A Siamese. A 60A snackbox on one side of the Siamese gives us 20A branch circuits. The other side we leave open for a large HMI or Tungsten Light. Now we can safely plug 1200 - 4000W HMIs (or even a 5k Quartz) into our own distribution anywhere in the house to balance the interior levels to the exterior. A good example of this approach is an American Experience program titled “The Most Dangerous Women in America” about Typhoid Mary that I lit for PBS. For part of her life Typhoid Mary was quarantined on an island in New York's East River. (Typhoid Mary in quarantine on an island in New York's East River. Note the view out the window of the East River shoreline at the turn of the century.) Because New York’s East River today looks nothing like it did when she was in quarantine, we used a 30' blowup of a picture of the East River at the turn of the century rigged outside the windows of a house in Arlington MA. As you can see by the production stills I have attached, the requirements of this production are very similar to what Pushparaj wants to accomplish. As you can see in the production still of the exterior of the actual location used for the quarantine island, we rigged a solid over the porch windows and the blow-up to keep the sun off both. That way we could light the blow-up and interior so that it remained consistent even though the sun moved on and off the porch in the course of the day. We had to strike a delicate balance between the interior and exterior levels. We wanted to overexpose the exterior by one stop so that it would look realistic and hide the fact that the exterior was a blow-up. To take the edge off the blow-up, we used a single scrim outside the window to help throw it out of focus. (The actual exterior of Mary’s cottage was the backyard of a house in Arlington Ma with a 30’ blow up of a picture of New York’s East River shoreline at the turn of the century.) To maintain continuity between shots, in this case we brought a 4kw HMI Par in a window on one side of the room as a sun source and a 1200 par through a window on the other side as a northern light source. We powered both heads off a dryer plug in the laundry room of the house using one of our Transformer/Distros. The two 2.5kw Par lights used outside to light the blow-up were powered by a Honda EU6500is through a second 60A Full Power Transformer/Distro. Since the Honda EU6500is could be placed right on the lawn, we were saved from running hundreds of feet of feeder back to a tow generator. (A child dying of Typhoid Mary filmed in a bedroom of the Ames Estate) We have been able to use this same basic package at numerous museums and historical houses throughout New England including Sturbridge Village. Fortunately for us, to make ends meet, many historical houses rent themselves out for events and weddings. For that reason, they usually have at least one updated service with 30 or 50 Amp 240 volt circuit for the warming ovens of caterers. (The New York City Health Inspector filmed in the library of the Ames Estate) Use this link for more production stills of PBS and History Channel historical documentaries shot this way. Guy Holt, Gaffer, Lighting and Grip Equipment Rental & Sales in Boston