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Which HMI AC/DC powered? Joker 200W?


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Hi

 

I'm trying to decide on which baby hmi to buy.

At the moment I'm leaning towards the Joker Bug 200w.

What are your thoughts on this light?

I'd rather pay a bit more and buy once.

The versatility of the joker seems great with or without the beamer so I can use my chimera or buy a pancake for it.

I'm also unsure of which of the 3 joker 200w models to get if I do go that way. They all have different beamers apparently and one has lenses aswell. If any of you have used them any comparisons would be great.

I've also got a set of dedos and love the build quality design.

Dedo have a 200w hmi as well but it doesn't seem quite as versatile and you have to buy two ballasts, a dc and an ac, where as the joker has one that does it all. But it is a very light weight kit and I want the kit to be as small and light as possible.

 

I mainly shoot in small 2 to 3 man crews.

I want to use it for exterior PTC's/ I/V's for a fill. I'm also hoping it will have enough grunt to enable me to shoot inside high rise offices where I live, shooting out the windows to the harbour view/ city view in the background, and match the exterior exposure.

 

Any advice much appreciated.

 

Cheers

Edited by Mike Nelson
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If you are going to put a chimera on it I think you might want to look at a 400W or even 800W HMI, Considering that you want to compete with daylight.

 

Can you ND the windows? in that case 200W can of course work.

 

Hey

I wouldn't use the chimera when trying to compete with daylight, just for other more light controlled situations.

Never have time to ND windows.

 

Cheers tho

Edited by Mike Nelson
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You can put a ceramic globe in the 200 Dedo and it becomes a tungsten fixture. That's a plus.

You should really demo one, I'm sure that will make up your mind.

 

Bill

Would love to demo both but when you live in New Zealand that can be a little tricky.

The closest K5600 joker dealer is Australia and there's no demo hmi dedos with the NZ supplier.

The beauty of a country of 4 million people. You could probably count on one hand the amount of these lights they'd sell a year!

But I agree the swapable ceramic/hmi bulb is a plus..

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200w isn't close to enough to compete with daylight whether you're indoors or out. You can get away with an 800w Joker Bug but you'll still be overexposing the background and/or underexposing your subject a bit. A 1200w HMI is the best option and the most you can get away with in order to plug into a standard outlet. Even better is having two 800w Jokers and firing them through a diffusion frame. The 1200w and/or the 800x2 gets you closer to a decent balanced exposure but you'll still have to be careful in choosing backgrounds that aren't screamingly hot, like white buildings or anything that is in full sun.

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200w isn't close to enough to compete with daylight whether you're indoors or out. You can get away with an 800w Joker Bug but you'll still be overexposing the background and/or underexposing your subject a bit. A 1200w HMI is the best option and the most you can get away with in order to plug into a standard outlet. Even better is having two 800w Jokers and firing them through a diffusion frame. The 1200w and/or the 800x2 gets you closer to a decent balanced exposure but you'll still have to be careful in choosing backgrounds that aren't screamingly hot, like white buildings or anything that is in full sun.

 

A Joker 200 won’t be enough to fill talent against windows and hold detail outside the windows. Without either gelling the windows or substantially boosting the light levels inside, or both, when you expose for your talent, your exterior will blow out. If you expose for the exterior to hold detail, your talent will be underexposed and become a near silhouette. Even a 1200W HMI won’t do it without gelling the windows. But, where a roll of 4 stop ND1.2 gel will set you back $140.00, it will be expensive and time consuming to gel the windows if there are a lot of them.

 

In my experience, if you can’t gel the windows you probably need at least a 4k HMI par to pick up the interior levels in wide shots. And, if you know how you can run a 4k off of regular wall outlets. For example, my company, ScreenLight & Grip, lit a segment of a special two-hour program for British Television’s Channel 5 that presented the same problem that you are facing.

 

piratefilmstrip1lg.jpg

Host June Sarpong interviewing a marine archaeologists

 

The show told the story of the Whydah - a pirate ship that sank off Cape Cod nearly 300 years ago. In a unique TV experiment, marine archaeologists on Cape Cod dove to the wreck to salvage pirate booty live on air. In addition to the dive on the wreck, the program also included specially shot dramatic recreations of the story of the Whydah’s notorious pirate captain Black Sam Bellamy. To link between the modern-day adventures of the marine archaeologists and those of Black Sam Bellamy, co-presenter June Sarpong hosted marine archaeologists and pirate historians from a makeshift studio under a tent situated on a bluff overlooking the dive site.

 

piratefilmstrip1.25lg.jpg

Host June Sarpong interviewing a marine archaeologists

 

Where they wanted the dive site to serve as a backdrop to the makeshift studio, the show's producers wanted the Salvage Ship to be seen clearly on the water in the shots of June and her guests. This requirement created a similar interior/exterior contrast problem to the one you are facing.

 

The task of balancing interior levels to exterior levels was further complicated by the fact that it was a clear sunny day. We rigged a couple of 4kw and 2.5kw HMI Pars into the frame of the tent in order to get them as close as possible to our subjects, but even then we didn’t have quite enough output to compete against the sun outside.

 

piratefilmstrip2.25lg.jpg

A 4k HMI Par was rigged overhead as a key for each subject

 

The final ingredient for success was a double net strung across the open backside of the tent. The net further reduced the contrast by bringing the exterior levels down and in line with the pumped-up interior. The trick in situations like this is to strike a delicate balance between the interior and exterior light levels so that the net disappears to the camera without the exterior becoming overexposed and losing important detail – the Salvage Ship out on the water in this case. Another advantage to netting the background is that it takes the hard edge off of HD. It creates the illusion of a shallower depth of field or the selective focus we associate with film.

 

piratefilmstrip3lg.jpg

A double net was stretched across the open side of the tent facing out onto the water.

 

Where it took a 4k Par on each of the talent, plus a double net across the back, you can see that you need a lot more light to balance interiors to exteriors than you will get from a Joker 200. The problem with using 4k HMIs is usually powering them. If you know how, you can plug them into wall outlets that are available on most locations.

 

Guy Holt, Gaffer, ScreenLight & Grip, Lighting & Grip Rental, Boston, MA

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...Another advantage to netting the background is that it takes the hard edge off of HD. It creates the illusion of a shallower depth of field or the selective focus we associate with film.

 

Damn! Nice idea Guy

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I'm trying to decide on which baby hmi to buy. At the moment I'm leaning towards the Joker Bug 200w.

What are your thoughts on this light?

 

Jokers are great lights, and have some very innovative accessories. The one drawback to Jokers is that their ballasts are not Power Factor Corrected. Their poor Power Factor causes them to use power inefficiently and the harmonic currents that they kick back into the power stream can have a severe adverse effect on the power waveform of some generators. Since the poor Power Factor of Jokers is commonly overlooked because of their small size, I would like to take this opportunity to explain it in detail and show how it might impact Mike’s decision.

 

If we look at the technical specifications for Joker Buglites, we see that the 120V electronic ballast that the Joker 200 uses has a Power Factor of .64. What that means is that it draws 2.6 Amps rather than the 1.66 Amps you would think using Ohm’s Law (W=VA.) The difference between the actual current drawn by the bulb, 2.6 Amps, and the 1.66 Amps a 200W bulb should draw using Ohm’s Law (W=VxA), is the difference between what is called “Apparent Power” and “True Power.”

 

If, in this case, you were to measure the actual current (using a Amp Meter) and voltage (using a Volt Meter) traveling through the cable supplying the Joker 200 ballast and multiply them according to Ohm’s Law (VxA= W) you would get the “apparent power” of the bulb (120V x 2.6A = 312W). But, if you were to instead, use a wattmeter to measure the actual amount of energy being converted into real work (light) by the ballast of the Joker 200 you would get the “true power” of the bulb which in this case is specified by the manufacturer as 200W. The ratio of “True Power” to “Apparent Power” is called the “Power Factor” of the light.

 

A favorite analogy electricians like to use to explain Power Factor is that if Apparent Power is a glass of beer, Power Factor is the foam that prevents you from filling the glass all the way up with beer. When lights with a low Power Factor are used, the distribution system must be sized to supply the Apparent Power (beer plus foam), even though only the True Power (beer) counts. With a Power Factor of .64, you must take into account that the Joker 200 ballast draws nearly 50% more power (312W) for it’s true power output of 200W.

 

Used on wall outlets, this relatively inefficient use of power is negligible because the power draw of Jokers are low to begin with. However, the greater Apparent Power of lights with a poor Power Factor must be factored when using portable generators. For instance, with a total load of 680W, you would think that you could operate a lighting package consisting of a Joker 400, a Joker 200, and a couple of 40W 1x1 Litepanels, on a simple two stroke 1000W generator from Walmarts (400W+40W+40W+200W= 680W.) But, in fact, you would overload the generator.

 

Like the Joker 200, the Joker 400 has a Power Factor of .64. You must therefore take into account that the Joker 400 ballast has an Apparent Power of 624W. Likewise with 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 these lights on a Walmart 1000W generator, the total Apparent Power of 1086W (624W + 75W + 75W + 312W = 1086W ), would overload the generator because the “continuous load” rating of the All Power America 1000W Generator sold at Walmart is only 850W.

 

The greater Apparent Power of Lights with a poor Power Factor is not the only consideration when operating them a generator. When you use lights sources like HMIs, Kinos, CLF lamp banks, and even LEDs, on generators it matters not only what type of ballasts the light uses, but also what type of generator you use to power it. The harmonic currents that ballasts with poor Power Factor kick back into the power stream can have a severe adverse effect on the power waveform of some generators.

 

Normally, when you plug a HMI, Fluorescent, or LED light into a wall outlet you need not be concerned about the current harmonics generated producing voltage distortion. 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, that inherently noisy loads placed upon it will not affect the voltage at the load bus.

 

wwaveform_elec_ballast.jpg

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.

 

However, it is an all together different situation when plugging non-Power Factor Corrected HMI, Fluorescent, or LED ballasts, into conventional portable generators. Given the large sub-transient impedance of conventional generators like Walmart’s 1000W generator, 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. Add to that, the fact that the original supply voltage waveform of a conventional generator, like Walmart’s 1000W generator, is appreciably distorted to begin with, and you have a situation where the return of any harmonic currents by an HMI, Fluorescent, or LED ballast will result in significant waveform distortion of the voltage at the power bus (see oscilloscope shots above.) The waveform distortion caused by these harmonic currents can have a severe adverse effect not only the generator, but also other electronic equipment operating on the same power. There is a video on You-Tube by a Lighting Designer by the name of Kevan Shaw that illustrates just this, but with CFL bulbs which have a similar Power Factor.

 

CFL_vs_Gen_Dem.jpg

 

In his You-Tube Video, “Compact Fluorescent verses the generator,” (available at

) Kevan Shaw compares the effect of equal wattages of CFLs and Incandescent lights on a small portable generator. In his test, he first operates a 575W ETC Source Four Leko with Quartz Halogen bulb on an 850W two stroke conventional gas generator without problem. However, when he tries to operate an equivalent wattage of CFLs (30-18W bulbs) the generator goes berserk. Only after turning off half the CFL Bulbs does the generator operate normally with a remaining load of 15 - 18W CFLs (270 W.) What accounts for the erratic behavior of the generator in this video under a smaller load of CFLs? It is a combination of the poor Power Factor of the CFL bulbs (.5) and the harmonic currents they generate.

 

Even though the 15 CFL bulbs have a True Power of 270W (15 x 18W = 270W ), the Watt indicator on Kevan's generator indicates that they draw twice that in Apparent Power (535W), or have a Power Factor of .5 (270W/535W =.504.) The fact that CFL bulbs consume double the energy (Apparent Power) for the 18 Watts of light (True Power) they generate, is only half the story here. Kevan Shaw’s video also clearly demonstrates the severe effect that loads - like CFLs, HMIs, Kinos, & LEDS - with leading power factor can have on the governing systems of conventional generators.

 

When Kevan turns off the 18W CFL bulbs one at a time until the generator stabilizes, he is not only demonstrating that 15 – 18W CFL bulbs has roughly the same Apparent Power (535W), according to the generator’s Watt meter, as a 575W incandescent light; but, also that the maximum Leading Power Factor load a 850W conventional generator can operate satisfactorily is 270 Watts (15 – 18W CFL bulbs). Looked at from another angle, 576 Watts of Apparent Power with a Leading Power Factor (16 - 18W CFL bulbs) overloaded the generator, while 575 Watts of Apparent Power with a Unity Power Factor (the 575W Quartz Leko) did not. What accounts for this difference? Since the load is almost the same (576 & 575 Watts of Apparent Power respectively), the only factor that can account for the generator going berserk with the equivalent load of CFL lights is the harmonic currents that they generate, that the Quartz Leko does not. Without a doubt, Kevan Shaw’s video is a clear demonstration of the adverse effect that harmonic currents have on the governing systems of conventional generators.

 

For the same reason that Kevan Shaw was not able to operate more than 270 Watts of CFL bulbs (15–18W bulbs) with a Power Factor of .5 on his 850W generator, Mike would not be able to operate the package of Jokers and LED lights on a 1000W conventional generator. 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 generators. For this reason, Mike might want to consider a 200W HMI like Arri’s Pocket Lite 200, that has Power Factor Correction, rather than the Joker 200.

 

Power Factor Correction can be of tremendous benefit when operating HMIs on portable gas generators because a PFC circuit realigns voltage and current and induces a smoother power waveform at the distribution bus. Arri’s PFC circuit successfully increases the power factor of the Pocket Lite 200 to .98, making it a near linear load. As a result, the light uses power more efficiently with minimized return current and line noise and also reduces heat, thereby increasing their reliability. A package consisting of an Arri Pocket Lite 200, a Pocket Lite 400, and two 1x1 Litepanels would operate on the Walmart 1000W generator without difficulty.

 

These power generation issues have been vexing set electricians for years. Use this link for an article I wrote for our company newsletter that explains the electrical engineering principles behind these issues and how to resolve them.

 

BoxBook.jpg

 

This article is cited in the just released 4th Edition of Harry Box's "Set Lighting Technician's Handbook" and featured on the companion website "Box Book Extras." Of the article Harry Box exclaims:

 

"Great work!... this is the kind of thing I think very few technician's ever get to see, and as a result many people have absolutely no idea why things stop working."

 

"Following the prescriptions contained in this article enables the operation of bigger lights, or more smaller lights, on portable generators than has ever been possible before."

 

The article is available online at http://www.screenlightandgrip.com/html/emailnewsletter_generators.html.

 

Guy Holt, Gaffer, ScreenLight & Grip, Lightng & Grip Rental in Boston

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I do carry a roll of ND.9 as well as a Westcott ScrimJim frame kit with a 2 stop net for these situations. Even with those working, an 800w JokerBug is barely enough.

 

Knowing that, I always have to wonder what on earth the purpose of a 200wHMI could possibly be. It's a cheaper HMI, for sure, but so what if you can't use it to gain the exposure you need?

 

The ND gel I do carry around isn't pristine so I use it mostly for BEHIND blinds or when I can keep the frame tight so as to not see any wrinkles. If I had to gel a massive window, then I would have production purchase the necessary rolls and adhesive to accomplish the task correctly. But, if this situation does come up, then we are usually into larger budget situations anyway (than my normal), so I'd likely have a grip/electric crew who would do that work. And if that's the case, then again, we're into larger units anyway and not even talking about scraping by with 800w or less HMIs.

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Thanks guys all very interesting stuff and a little more complex than I originally expected with the "power factor" etc.

I just wish I could trial some different models to compare. Might have to fly to US to do so though!

I think the netting idea could be a good option for various shoots and is lightweight and cheap.

The thing is, I can almost get enough grunt out of my kino diva 400 on an overcast day to match the exterior background to the interior I/V I'm shooting and I would have thought and looking at the photometric comparisons the 200W Joker seems to have more grunt (am I reading them wrong?).

The kino is obviously the key and is usually about1.5 to 2 metres away. The windows in a lot of the buildings we film in do have a tint to them (maybe 1 to 2 stops at a guess).

 

Also in regards to getting some nice fill when shooting exterior PTC's/ I/V's, ideally I'd probably use a reflector, but I live in one of the windiest cities in NZ and your lucky if you can get 1 person to try and hold it still let alone 2.

Are there any good, portable, light 1 person setup flecky systems? I'm thinking stands and grip heads etc. A solid poly would probably break and I couldn't fit it in my mid size suv.

 

Other options?

 

Cheers

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http://www.k5600.com/products/jn200/images/location.jpg

This photo is from the K5600 website.

To me it looks like a joker 400W with the ac power supply connected to an inverter?

Again I'd really like a field/ DC option and I think 400w is the biggest I could go without a genny?

The fill on the interview subjects face looks exactly like what I'm after. It does look like an overcast day in the background.

Thoughts?

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http://www.k5600.com/products/jn200/images/location.jpg

This photo is from the K5600 website.

To me it looks like a joker 400W with the ac power supply connected to an inverter?

Again I'd really like a field/ DC option and I think 400w is the biggest I could go without a genny?

The fill on the interview subjects face looks exactly like what I'm after. It does look like an overcast day in the background.

Thoughts?

 

That photo is of a 200w, specifically the Joker News 200. Noone touched on the different type of Jokers for you, so let me go over that. All Joker 200s have the same head, just different reflectors. All can become the "Bug" light for Chimeras. The Joker Bug 200 has a normal, fixed focus Par head that uses lenses to adjust the beam angle/shape. The Joker News and Joker Evolution are zoomable par fixtures that have no lenses. The lensless models have a small range of 16-45 degrees. The News version has a fancy zoom feature that allows you to easily slide a lever and change the angle. The Evolution is basically the same thing but it rotates only on the reflector mount, requiring you to loosen the (probably really hot) mounting screws. The Evolution is the least expensive of the bunch and was designed for budget reasons. The Evolution kit is $1000 US cheaper than the normal Joker 200. The regular Joker Bug does not have a particularly pretty beam, but can put out some serious, narrow light if needed. The News and Evolution don't put out quite a much from the reflector, but is a smoother beam that doesn't require much of anything to look ok - you can shoot it right at a subject if needed (strong shadows however - ok for news, not ok for most everything else).

 

One thing noone has thought about is that office windows, especially high rise buildings are often tinted - many VERY tinted. Who wants to look/feel the open sun all day? That's the reason your Diva is almost bright enough and a 200w par would be great. The Diva 400 puts out around 80fc at 6ft, where the Joker puts out 700-2100fc. You'll probably want to soften that up some but you have the choice of making it as soft as the Diva (and a bit brighter) or using somewhere in between to kick things up. The Joker bounced into a 4x4 of something would be pretty nice.

 

The photo you linked to is def the Joker News 200. It looks like they are shooting (pun intended) the poor guy right in the face with no diffusion, hence how they are able to get some decent exposure outside. While I think the Joker 200 would be a good option inside, unless it's less than 6ft and shining right in your subjects face - it's not going to cut it. In that case, I would agree with the others and say a standard 1200w par is the minimum outdoors.

 

I have a couple 200w pars in my rental stock, and they are very popular so lots of different people find them useful. Many times they go out with Kino Flos and bigger HMIs and are used for highlights, backlights, fill, etc.

 

I would not worry about the power factor of these lights unless you need to plug a whole bunch of them into a single circuit, house or generator. 2.6 amps vs 1.6 amps for this situation gets a big fat "who cares" from me.

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I would not worry about the power factor of these lights unless you need to plug a whole bunch of them into a single circuit, house or generator. 2.6 amps vs 1.6 amps for this situation gets a big fat "who cares" from me.

 

No argument here that the greater Apparent Power of Lights with a poor Power Factor is negligible when using one light to fill someone against the windows of a high rise. The Leading Power Factor of sources like HMIs, Kinos, CLF lamp banks, and even LEDs, is a factor, however, when using them on generators. For the same reason that Kevan Shaw was not able to operate more than 270 Watts of CFL bulbs (15–18W bulbs) with a Power Factor of .5 on his 850W generator, Mike would not be able to operate just a couple of Jokers on a 1000W conventional generator. The harmonic currents that ballasts with Leading Power Factors kick back into the power stream can have a severe adverse effect not only the generator, but also other electronic equipment operating on the same power. The adverse effects can take the form of overheating and failing equipment, efficiency losses, circuit breaker trips, excessive current on the neutral wire, and instability of the generator voltage and frequency. Harmonic noise can also damage HD digital cinema production equipment, create ground loops, and possibly create radio frequency (RF) interference.

 

These adverse effects, 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 generators. Mike would not have the same issues with the Power Factor corrected Arri Pocket Lites.

 

While I think the Joker 200 would be a good option inside, unless it's less than 6ft and shining right in your subjects face - it's not going to cut it. In that case, I would agree with the others and say a standard 1200w par is the minimum outdoors.

 

Once again, it would be advantageous to have Power Factor Correction in the 1200 ballast because it would enable you to safely plug it into a standard 15A wall outlet, or operate it off of a small Honda Inverter generator. Drawing only 11 Amps (verses the 18 Amps required by standard electronic ballasts), a PFC 1200W ballast will enable you to safely plug a 1.2 HMI Par into both 20A, as well as the more common 15A, wall circuit. Where you quite often don’t know the rating of the wall circuit that you are plugging into, the lower draw of a PFC 1200W ballast will ensure that it will work where a standard electronic ballast will not.

 

And, since it draws only 11 Amps, a PFC 1200W ballast will run more reliably on a Honda EU2000i as well. This combination can be particularly effective for lighting on remote locations. At only 46.3 lbs, you can grab the Honda EU2000i Generator and set off. And at, only 34 dBA at 50 ft. with a 1.2kw load, the Honda EU2000i Generator is so quiet that it won't be picked up on your soundtrack when used a short distance away.

 

Guy Holt, Gaffer, ScreenLight & Grip, Lightng & Grip Rental in Boston

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