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I was just wondering after searching a lot around on eBay and other secondhand websites and finding many different cheap lights, wether or not they might be fully functional and suitable for a modern production. As you know, new lights and lighting equipment are expensive, especially Arri's and other industry standards. But older used lights go down on eBay for dirt cheap. I am interested in all opinions on pros and cons with older lights and equipment as compared to new expensive ones. (Mostly considering indie productions)

 

Thanks alot :)

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+1, Certainly don't even turn on an old mains unit without checking the wiring for condition, continuity and good earthing, and the fixings for security.

Wiring near the bulb could have become brittle with heat, as could mains leads more than about 40 years old which may be made of a rubbery material which can crack.

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Thanks a lot. I know at least one electrician, so that would be no problem. As of now I will probably be looking around some more for the lights I want, but you have really made it easier to search for them. Great to know that old lights will be just as great, only considering the more technical part of it. Also, I love the tungsten look as opposed to led so simply another bonus there. Thanks again for quick answers

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Anything tungsten will generally be ok. Used Kinos are also still worthwhile (and i suspect will be going cheap as many people convert over to LED). Granted, a Kino Ballast may die out but you can still buy new ballasts if need be. I'd be careful with HMIs, though they are useful, and the 1.2 and 2.5 PARs are coming down in value as people move to M18s almost exclusively but it's not something you can fix yourself (ballast) so you'll need to know someone who can fix it for you. I also tend to avoid used off brand LEDs, as chances are they're crap .

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  • 2 weeks later...

.... I'd be careful with HMIs,...

 

Given the evolution of HMI technology you can easily get stuck with a lemon if you are not careful. In head design you have (in chronological order) Fresnel, Par, and the new CAD designed ARRIMAX reflectors. The basic difference in head design between a Fresnel and Par is that a Fresnel gives you less output for the wattage, but the light is crisp and you will be able to cut a clean shadow edge. The Par on the other hand gives you more output, but the light is sloppy and you will not be able to cut a clean shadow edge. The newest CAD designed ARRIMAX reflectors give you nearly the crispness of a Fresnel, and more output than a Par since they do not use spreader lenses like a Par head.

 

HMI globes were originally double-ended and then single ended globes were introduced. The newer single ended globes put out approximately 10% more light than the older double end globes and allowed manufacturers to make a more compact head design. The newer single ended heads are smaller and lighter for that reason. Beware the older style par fixtures that use a bulb that incorporates the par reflector within the bulb – they are hard to come by and quite expensive.

 

The history of HMI ballast design is not quite as linear as that of head design in that its’ progress is characterized by the proverbial two steps forward while making one step back. When electronic square wave HMI ballasts came on the market, they were at first thought to be the solution to all the problems inherent in running HMIs with magnetic ballasts on portable generators. Since they are not frequency dependent, it was thought at first that electronic square wave ballasts would operate HMIs more reliably on generators – even those without frequency governors. By eliminating the flicker problem associated with magnetic ballasts, they also eliminated the need for the expensive AC governors required for flicker free filming with magnetic HMI ballasts and portable generators. 

For these reasons, as soon as electronic square wave ballasts appeared on the market, many lighting rental houses replaced the expensive crystal governed Honda EX5500 with the less expensive non-synchronous Honda ES6500. The theory was that an electronic square wave ballast would operate reliably on a non-governed generator and allow filming at any frame rate, where as a magnetic HMI ballast operating on an AC governed generator allowed filming only at permitted frame rates.

 

In practice, electronic square wave ballasts turned out to be a mixed blessing. The leading power factor caused by the capacitive reactance of the new electronic ballasts proved to have a more severe effect on conventional AVR generators than did the old magnetic ballasts. 

Since magnetic ballasts worked reasonably well on AVR generators with governors, in the past, attention was only given to portable generator features such as automatic voltage regulation, speed regulation and AC Frequency. But, given the leading power factor of electronic HMI ballasts and the problems they cause, an increasingly more important feature today is the quality of the generated waveform and the impedance of the power system. For this reason, it is imperative that today’s power generation and electrical distribution systems be designed for capacitive lighting loads, not just inductive lighting loads.

 

This is especially true of the systems to be used in low budget independent production because these productions have traditionally relied upon portable gas generators that are more susceptible to the adverse effects of harmonic distortion. These productions are also increasingly embracing the use of HD digital cinema production tools, like inexpensive HD camcorders, laptop computers and hard drives, that require cleaner and more reliable power on set to operate effectively.

 

If some of this terminology is foreign to you, I would suggest you read an article I wrote for our company newsletter on the use of portable generators in motion picture lighting. In it I cover the evolution of HMI ballast technology, basic electrical engineering principles behind ballast Power Factor, harmonic distortion, and how it adversely affects generators. The article is available at http://www.screenlightandgrip.com/html/emailnewsletter_generators.html.

 

 

Guy Holt, Gaffer,

ScreenLight & Grip

Lighting Rental & Sales in Boston

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