Home of Professional Cinematography since 1996


Fluorescent Lamps


I'm interested in experimenting with some fluorescent, but don't have access or budget for Kino's... So, I'm thinking of going the all-american way and rigging something. But I have some questions..What makes Kino's different from regular fluoro's, besides the better CRI of the tubes.. And can't I find commercial tubes that are decent now? My stuff is all for transfer, so I have room for colour correction. Do Kino's have more output?Anyone have any tips for building my own? I just bought an in industrial fixture and some 90 CRI tubes to play with. I'm thinking of taking the ballasts out and mounting the sockets to a board.. then having a detachable cable between the two

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Can I buy different ballasts and sockets for building my own?


Thanks for any and all answers to this myriad of questions!


Bobby



The great thing about KinFlo's is how light, modular and convenient they are to mount.
Granted, they are flimsy but the convenience of being able to strip away the guts and just mount the tubes is wonderful. And the hi-lo ballasts are nice . I know someone who tried to do what you describe above and they just about killed themselves. It was a wiring/end-socket screw up that led to a severe shock.


I think you need to be very careful if you are trying to design your own fixture with a remote ballast.In any case, you should go with the Optima 32 (or Chroma 50) tubes. There are refinements to the ballasts and cabling with KinoFlo's but at the heart of the system there are great tubes. You should start with those in some ready made fixtures before going too homespun with the connectors, cabling and remote ballasts.Have you priced the KinFlo end connectors? They used to be very pricey but maybe that has changed. They are a key part in the ease-of-use of a KinoFlo.


David Perrault



The CRI is the "cheval de Troie" for the industrial fluorescent manufacturers.


CRI is not it. There are lots more factors such as the temperature (in & out of the tubes), the energy spectral distribution, the efficiency, the type of ballast, the phosphors quality, the quality of the connectors...What you won't find in a commercial tube is a coherent spectral energy distribution, in other words, filtering correction will be hard to solve because there will be several discrepancies in the yellow and green, and it will be very very poor in the red and in the blue. Also watch out for UV radiation. You could use a gel, but you will soon have colour shift related to the increase of temperature in the tube.


Today (2003) there are only two alternatives :


*KinoFlo - www.kinoflo.com


*Softlights - www.softlights.com


First of all, get a good tube (Kino or Softlights), otherwise you will waste your time . Having the ballast separate from the fixture is only necessary if your ballast is noisy or very heavy, otherwise there is no advantage to it. Be aware that commercial ballasts are cheap for one reason: they are cheap! You may run into flicker problems, noise problems, reliability problems and consistency problems.


A lot of problems...By the way, I love fluoro's.


Sebastien Laffoux Softlights



This is simply not true.


Having filmed hundreds of thousands of feet of film with fluorescent light sources, I have to differ. I love Kino-flo's (I even have a Kino Flo jacket:-)) and I have on occasion used Softlights, notably in the United Arab Emirates.


I worked extensively with the Softube 1500 ma fixtures and tubes in the 80's (my partner in Liberty Lighting designed and marketed them way back when)...and ...more importantly, I have relamped hundreds of fixtures with Optima 32's. Chroma 50's. Vita Lites, etc. Duro-Test makes the Optimas and other color correct bulbs. They are a New Jersey based lamp manufacturer and they formulated the lamps we used for Softubes (daylight and tungsten) and have done so for other manufacturers as well. Their lamps are designed to be used in "normal" fixtures, and if you over-drive them (using a bigger ballast than design specs call for) you will raise the temp in the tube and get stronger green spikes (from the low pressure Mercury that makes them work in the first place) and possibly more UV.


I have built a number of home-built fixtures over the years and for an IMAX film back in the early 80's we lit an entire 747 interior with those cheap electronically ballasted shop lights you can buy at any Home Base-Home Depot. I have also lit large scenes with WWX lamps - Warm White Deluxe was a colour that was in vogue in the early 80's that gave reasonably good output, was a bit higher than 3200 - probably 4300 or so, and could be corrected for green with 1/4 minus green . Someone else will have to back me on this as I am away on location in a desert and without my references, but I believe that Optima 32's require nor correction with most modern colour neg, Vita Lites and Chroma 50 are both daylight balanced but one of them could use between 1/4 and 1/8 minus green while the other is OK. I have found that you are probably better off just s lightly under correcting fluorescents than over, but you should test.


You can buy the different stocks in 35mm still cartridges and shoot a gray and McBeth with different corrections. If you use RGB lab, you will find that they will not time to the gray scale but rather print at 25 25 25 (I believe) but multiple tests on one roll will show relative differences . I have been too busy to post but could not let this go by unchallenged.


Mark "CML thrives on differences of opinion" Weingartner



If you choose to build your own as I did, stick to the four-foot size for easy of use. A standard magnetic ballast will run you about $10 from the hardware store. BTW, the KinoFlo electronic ballast lets you shoot at any speed flicker free, using a magnetic ballast limits you just like using a magnetic (non flicker free) ballast does with an HMI. You can use regular 18 gauge zip cord wiring and for connectors, I use standard household 2-prong Edison quick-connects, the sockets of which will clip onto the prongs of a flo tube just fine.


Make sure to use some vastly different kind of connector on the other end where the wire connects to the ballast, lest some intrepid assistant tries to plug it into a standard 120vac wall outlet. This will certainly fry your flo tube and poses a serious threat of explosion, with the accompanying flying glass.This is not for a project for someone who knows little about electricity or wiring. But if you don't have the experience yourself, you could ask a decent gaffer and he/she should be able to whip one up for you.


What I like about my "Mitch Flos" (also dubbed "Kinda-Kinos" by a gaffer friend), is that you can attach a wiring harness or virtually any length between ballast and bulb, and between bulb and bulb. This means you can stick the ballast far from anywhere its hum might bother the sound department, and you can rig the bulbs in any configuration without dealing with the short spread standard Kino wiring harnesses will allow. I've lost count how many times I've stick these things under bar counters to light up the bartender and all the plumbing and drinks.


Mitch



You can also high frequency electronic flicker-free ballasts from companies like Magna Tek. The method Mitch suggests is often done with wiring two duplexes onto the ballast enabling one to run two four foot tubes off the ballast. Each plug on the duplex goes to a lamp end and is wired to the ballast respectfully. I have a few of these ballast kits lying around but rarely use them with Kinos available. But Mitch's words of wisdom cannot be stressed enough. This is NOT for an inexperienced person to wire up. Use only a qualified electrician to build this for you. Mitch - I wonder if these kits are a NYC phenomenon as I rarely have seen them used elsewhere. I think they came from the days before Kinos in NY for independent filmmaking. That's where I learned how to build them.


Jim Sofranko NY/DP



Mark is absolutely right about Optima 32(00)s, Chroma 50s and Vitalights. Ordinary fluorescent tubes can also be used to key, fill or highlight interiors that are lit with fluorescent that are impractical to re-lamp with Chromas or Optimas.


The trick is to match the existing lamps exactly. That is if the supermarket is lit with Sylvania Warm White Deluxe tubes you must use the same. The overall colour correction can be applied to the entire scene.


The other thing to do is to let the background overexpose slightly, 1/4 to 1/2 stop. If the background is under exposed the green cast from the flouro's will require that the foreground scene be overcorrected with magenta.Also Mitch is right on with the testing advice. GE and Osram/Sylvania publish guidelines for colour correcting nearly all of their products.


This will give you a good point of departure for your tests or a life-saver for last minute industrial filming. Talk to customer service. Newer fluorescent technology is rapidly catching up with Kino-Flo.


The newest T-8 lamps have extremely high colour rendering indexes when used with electronic ballasts. You should be aware that not all electronic ballasts are equal. There are noise ratings for them as well as efficiency ratings. The newest are virtually silent. However, most electrical supply houses only stock the most popular. I am told that Motorola makes the best, which may mean the most reliable.


If you are dealing with small quantities, it is usually cheaper to cannibalise fixtures for parts, than it is to attempt to build fluoros from scratch

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Good places to get acquainted with part nomenclature are :


McMaster-Carr - www.mcMaster.com  and MSC - www.Mscdirect.com


Brian "Now flicker-free" Heller



Actually, no. The DuroTest Optima 32s and VitaLite 55s are Kino Flos. Kino used to manufacture their own tubes, but they don't do that any longer. They purchase their tubes from DuroTest. They're the same thing. If you're making your own Kinos - it's best to track down a high frequency ballast. They're not cheap, but they'll certainly do the trick. Another great benefit of Kinos are the plastic coatings on the tubes which make them much more durable and easy to handle. I've had a couple of Kinos break in my hands over the years and no damage whatsoever -- try that same trick with a regular flo tube and you're not going to be a happy camper... If you're attempting to coat them yourself - be sure to leave enough room between the glass and the plastic for air flow - lack of air flow can cause the tubes to overheat and give you freaky colour spikes.


All the best,


Jay Holben
Director of Photography Los Angeles, CA
http://users.aol.com/adakinprod



I was told recently by a rep at Mole Richardson that DuroTest went out of business. I checked on the web and found out that GE will now make Vita-Lites, but will not continue to use the Vita-Lite name.


Jessica Gallant
Director of Photography and Listmum Studio City, CA USA



The plastic sleeves can be purchased at any good lighting/electrical store.


Jim Sofranko NY/DP



From my experimentation and use, if you can get yourself a high frequency electronic ballast (some that can be configured for a dimmer pot in line - something most kinos don't have) that has a frequency of about 25Khz then this will function like a kino. The secret is in the tube. I have used kinos side by side with standard battens and although kino says that they will have less output and will shift towards green, I have had no problems. You can use other tubes 90 CRI and above, but I think you will find in most cases that they have a lower lumen per watt output than the kino tubes.


Nick Paton
Director of Photography



I do not believe this is totally true...that is to say, yes, Duro Test has been making some of Frieder's tubes, but no, they are not the same thing. Kino Flo ballasts run approx 900milliamps through a four foot tube which is considerably more than a standard F40 ballast lets through a four-footer. The Optimas and Vita-Lites are formulated for standard ballasts, and if you over-drive them to 900milliamps with a high output ballast, they may give you extra green. Likewise, if you put Kino tubes made for their high output ballasts in a standard fixture, they might end up green-deficient.


Fluoro's make their colours with a combination of a witches' brew of phosphors coating the inside of the tube and the light emanating from the low pressure Mercury arc running down the tube (which is what excites the phosphors in the first place.) More current yields more output, but it adds green as the additional output from the arc rises disproportional to the increase in output from the phosphors. Tubes that are made to run on 800milliamp (so called HO) 900milliamp (KIno's) or 1500miliiamp (, VHO, SHO, Softubes) are formulated for the current they are using.


A note on ballasts :


I researched electronic ballasts some years ago and discovered that there were a number of electronic high freq. ballasts on the market, but they were biased towards the "same light for less current" side of the market, rather than the "more light for the same current" side of the market. They are selling energy efficiency and lower lamp replacement costs, not more light. Frieder's ballasts are high output, as are some of the other manufacturers' "made for movies" units - the commercial lighting industry does NOT provide higher output options for us. In short, it may look like you could save a lot of money by building the same thing that Flo-Co, Kino-Flo, etc. build for less by buying off the shelf parts... ...you may well end up with very useful fixtures that do what you need for a lot less, but you may not end up with the same amount of light per tube as these guys deliver.


Mark H. Weingartner
Lighting and VFX for Motion Pictures


According to my ASC manual, which I just got back from someone who borrowed it here Optima 50's and GE Chroma 50's require the same correction, while Vita Lites require less blue but more minus green to get to true daylight. David Quaid did extensive testing on this stuff which is very useful to read (I have the old Red ASC manual as my "new one" I assume this info survived to the green edition.) It is worth doing tests, as stocks' sensitivity to various wavelength spikes varies a lot.