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Kino Flo tubes in standard striplight fitting?


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#1 Peter Anderson

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Posted 29 December 2007 - 05:22 PM

Can put Kino Flo tubes into domestic Fluorescent fittings I can get at my local hardware store?
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#2 David Mullen ASC

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Posted 29 December 2007 - 06:22 PM

Yes, but you have to match the type of connectors. Most Kino tubes are the old 2-pin T12 but they are now making them in the newer T8 style:

http://www.kinoflo.c...20Match.htm#900

Most of the basic hardware store fluorescent shop lights use T12 connectors.
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#3 Peter Anderson

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Posted 29 December 2007 - 06:46 PM

Im not very technically proficient when it comes to light fittings. Do i have to consider flicker problems? If not, when does the issue of flicker apply? Sorry about the garbled tone of this question, the issue of flicker confuses me.
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#4 David Mullen ASC

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Posted 29 December 2007 - 07:09 PM

Most hardware store fluorescents have magnetic ballasts, so you have to shoot at crystal-sync at "safe" speeds for 60 Hz (in a 60 Hz country like the USA.)
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#5 Peter Anderson

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Posted 29 December 2007 - 07:15 PM

Thanks David,
Wheres the best place to swot up on the subject of flicker? I definately need to have a basic understanding on the subject.
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#6 Freya Black

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Posted 29 December 2007 - 07:39 PM

Im not very technically proficient when it comes to light fittings. Do i have to consider flicker problems? If not, when does the issue of flicker apply? Sorry about the garbled tone of this question, the issue of flicker confuses me.


Apparently there is less flicker if you use what are called High Frequency ballasts. It really depends on the kind of ballasts in the fittings. More modern fittings tend to be high frequency but it's something you definitely need to check. If you shoot in old buildings tho, the existing fittings are usually nasty old things they havn't changed since the 70's or something. Well it depends on which old buildings but I've run into a few.

Also watch out for the term "strip light", I've seen this used to mean some other kind of weird lighting that comes in tubes but basically is something like a tubular tungsten lightbulb. This fitting obviously won't take flo's. They are preety weird and I've never got my head round them, but they must be fairly common as they sell the tubes in Morrisons!

If you are shooting on daylight balanced stock such as 250d (which I get the impression you aren't but I thought I would say anyway!) there are also now somewhat cheap daylight balanced tubes available. You have to get ones with what is called a high CRI rating. If you search the forum you will find all kinds of neat stuff about diy flo's. Obviously there aren't cheap tungsten balanced tubes out there to the best of my knowledge, so in that situation you would probably have to use real kino tubes.

There are also some really intresting flo based worklights kicking about at the moment complete with tripod and everything. I've been eyeing them up whenever I walk past construction sites that use them. I've no idea what kind of ballast they have tho.

Lastly before shooting film it's worth looking on a video camera or the video tap to check for flicker. If you see it on the video camera, you will almost certainly get it on film too, so it's worth checking as an extra safeguard.

love

Freya
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#7 David Mullen ASC

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Posted 29 December 2007 - 08:12 PM

http://en.wikipedia....dium-arc_iodide
http://www.cely.com/flickerfree.html
http://www.cinematog...IFlickering.htm
http://www.cinematog..._Time_Lapse.htm
http://members.aol.c...ver/flicker.htm
http://www.bs-ballas...ht-englisch.PDF
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#8 Jaron Berman

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Posted 29 December 2007 - 10:43 PM

Modern "High Frequency" ballasts are electronic ballasts, similar to those within the Kino fixture itself. Older style ballasts, known as "instant start" or "quick start" ballasts are magnetic, meaning they pulse at the line frequency of the power they're wired to. In the U.S. they"flicker" 60 times/second, in the U.K. is 50/sec (50 hz). High-frequency ballasts also flicker, but 40,000-60,000 times / second, so it's very unlikely you'll be shooting fast enough to catch a ballast-related flicker on electronic ballasts.

If you remove the covers of the lights you're re-lamping, you can read the ballast to figure out what you have. Don't assume every fixture has the same ballast! Especially in large offices, as lights have problems and ballasts burn out, they get replaced (usually with the cheapest pieces possible). Also note that electronic ballasts are significantly more efficient than magnetic ballasts, and you will almost always see a large gain in output from the same tube if hooked to an electronic ballast.

As for flicker, if you're shooting at an off speed (see Davi'd link to the safe framerate tables), you'll probably see some. However, with older tubes you may ALSO see flicker, due to the ballast being unable to sustain the plasma within the tube. This can happen even with electronic ballasts, so be aware of the age of the tubes you're putting in. Fluorescents have mercury in them, which brightens the output of the lamp, and helps create the correct frequency of radiation to excite the coatings inside the tube. As the tube ages, the mercury migrates into the coatings and glass, away from the electrodes and causes unstable "burn" of the tube, which can appear as a color shift or flicker.


Freya also makes a good point - Kino is not the only game in town when it comes to color-correct tubes. Find a lighting wholesaler that deals in fluorescent, and ask what they have in the way of high (>89 or >91) CRI tubes of the fitting and color temp you're looking for. Chances are, they'll have about 5-6 different tubes that fit your needs, and prices significantly cheaper than Kino.
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#9 Tim O'Connor

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Posted 30 December 2007 - 02:15 AM

Modern "High Frequency" ballasts are electronic ballasts, similar to those within the Kino fixture itself. Older style ballasts, known as "instant start" or "quick start" ballasts are magnetic, meaning they pulse at the line frequency of the power they're wired to. In the U.S. they"flicker" 60 times/second, in the U.K. is 50/sec (50 hz). High-frequency ballasts also flicker, but 40,000-60,000 times / second, so it's very unlikely you'll be shooting fast enough to catch a ballast-related flicker on electronic ballasts.

If you remove the covers of the lights you're re-lamping, you can read the ballast to figure out what you have. Don't assume every fixture has the same ballast! Especially in large offices, as lights have problems and ballasts burn out, they get replaced (usually with the cheapest pieces possible). Also note that electronic ballasts are significantly more efficient than magnetic ballasts, and you will almost always see a large gain in output from the same tube if hooked to an electronic ballast.

As for flicker, if you're shooting at an off speed (see Davi'd link to the safe framerate tables), you'll probably see some. However, with older tubes you may ALSO see flicker, due to the ballast being unable to sustain the plasma within the tube. This can happen even with electronic ballasts, so be aware of the age of the tubes you're putting in. Fluorescents have mercury in them, which brightens the output of the lamp, and helps create the correct frequency of radiation to excite the coatings inside the tube. As the tube ages, the mercury migrates into the coatings and glass, away from the electrodes and causes unstable "burn" of the tube, which can appear as a color shift or flicker.


Freya also makes a good point - Kino is not the only game in town when it comes to color-correct tubes. Find a lighting wholesaler that deals in fluorescent, and ask what they have in the way of high (>89 or >91) CRI tubes of the fitting and color temp you're looking for. Chances are, they'll have about 5-6 different tubes that fit your needs, and prices significantly cheaper than Kino.


In terms of light output for the same size/wattage tube, is it primarily/solely the ballast that makes the difference
or do the more expensive Kino tubes have different technology that gives them greater output than a wholesaler's
or home supply store fluorescent tubes with acceptable CRIs?

Would a low budget, do it yourself person, somebody with more time than money,
do best by buying electronic ballasts at a home supply store and
non Film industry brand tubes with good CRIs?
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#10 Jaron Berman

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Posted 30 December 2007 - 04:34 AM

Ballasts make a huge difference in terms of output. however, different tubes use different phosphors, and thus have differing output. Kino tubes tend to be dimmer than off-brand tubes, due to their particular phosphors. BUT, note that most lower CRI tubes use a huge spike in green output (an easy color to make using this technology) to pump their output. Your eyes "white balance" it out, so it looks white, but that's why you see a green tint on film. Video can generally do a good job of balancing this out, or you could gel it out or on-camera filter it out depending on how much light you can lose and time you can take to do the corrections. The advantage to the gel/filter/white-balance method is that you could buy $1 tubes instead of $20 tubes.

If you're re-lamping a whole room full of fixtures, it may save you time to just color-correct the green tint out. If you're looking to build a couple of cheap flo's, then getting electronic fixtures from a home center will work with just about any tubes that fall in the wattage range, including inexpensive daylight or tungsten-balanced high CRI tubes.
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#11 Peter Anderson

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Posted 30 December 2007 - 06:59 AM

A sincere and gratefull thank you to all the great responses. A great deal has been cleared up for me.

My curiousity on the subject stems from the need to have a compact overhead soft source where there is very little headroom available. In my tests shoots Ive been Using a domestic fluorescent fitting secured to a boom arm overhead and then gelling additional fresnels with plus green. Due to budget constraints Ive only been taking photos so far but have a test shoot on an Arriflex SRII next week to try out my various options and check for flicker.

Im not a fan of heavy postwork and am particular about colour and tone in my work. This is the main reason why I want to avoid just taking the green out of the telecine. I have considered standard daylight tubes but my only experience using an apparently 5600k balanced bulb still produceds a murky green tinge.

I think Ill swot up on the subject and use something similar to this:

http://www.alertelec...light-fittings/
Standard-Fluorescent-Light-Fittings/Fitzgerald-4ft-Twin-Fluorescent-Fitting-FZLPT236.asp

It obviously wont be great quality but for under £100, a 4ft 2bank DIY kino would be a great solution. Take that, mount it to some MDF and screw on a fire door handle and it would have endless applications.
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#12 Freya Black

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Posted 30 December 2007 - 07:26 AM

I guess you could also use daylight balanced tubes and then use an 85 filter on the camera or something and shoot on tungsten stock still!

I wasn't very awake last night when I posted and I'd been watching some depressing documentarys too so I didn't think of it then, mind on other things! ;)

love

Freya
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#13 Michael Nash

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Posted 30 December 2007 - 03:23 PM

Im not a fan of heavy postwork and am particular about colour and tone in my work. This is the main reason why I want to avoid just taking the green out of the telecine. I have considered standard daylight tubes but my only experience using an apparently 5600k balanced bulb still produceds a murky green tinge.


If you want to remove the green in camera instead of telecine, you'll need a CC Magenta filter or an FL-B or FL-D, depending which film stock balance you're using.

http://www.camerafil...m/pages/fl.aspx

http://www.tiffen.co...F...t and Other
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#14 Tim O'Connor

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Posted 30 December 2007 - 08:59 PM

If you want to remove the green in camera instead of telecine, you'll need a CC Magenta filter or an FL-B or FL-D, depending which film stock balance you're using.

http://www.camerafil...m/pages/fl.aspx

http://www.tiffen.co...F...t and Other



Isn't it preferable, if feasible, when using fluorescents, to have tubes with the least green as opposed to
tubes with an amount of green so high that it must be removed because removing the green with a camera filter
or later in post, tends to give flesh tones a grey tinge? That's what I've heard, although I'm still interested in an
inexpensive set up that I could use for certain video projects if I could white balance acceptably.

Maybe buy the tubes designed for film industry use and build the rig with electronic ballast and other supplies
from home supply store? I do a lot of personal projects, short narrative pieces mostly, and I usually don't have
to rent lights because I have a good amount of rag tag units that I've picked up along the way, although I tend to
not use them on jobs because, although I can use them well, I know that they can seem to be too strange and
unfamiliar an assortment to many clients.

Jaron, thanks for the ballast info..
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#15 Freya Black

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Posted 31 December 2007 - 05:13 AM

Isn't it preferable, if feasible, when using fluorescents, to have tubes with the least green as opposed to
tubes with an amount of green so high that it must be removed because removing the green with a camera filter
or later in post, tends to give flesh tones a grey tinge? That's what I've heard, although I'm still interested in an
inexpensive set up that I could use for certain video projects if I could white balance acceptably.


In the past I've mostly heard of people using minus green gels on the actual lamps rather that putting a filter on the camera, so I guess if you had daylight balanced tubes that did have a green spike you could gel it out but then it depends on how much gel is going to set you back vs better tubes.

Recently I've seen these fld filters and stuff around on ebay a lot and been quite curious about them as I know nothing about them! Do they correct to tungsten? Surely flo's vary in colour temp anyway unless you have special tubes? Would like to know more about these filters!

Mostly I would prefer to filter the lamps than the camera, as it's more stuff in your optical path but I guess sometimes that isn't practical.

love

Freya
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#16 David Mullen ASC

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Posted 31 December 2007 - 12:04 PM

Filtering the camera only works when the entire scene is lit by one type of light that needs correcting. Doesn't work in mixed lighting conditions, hence why you gel the light itself.

The FL-B and FL-D filters were really designed to deal with the classic Cool White tubes. Cool Whites are around 4800K plus Green, so the FL-B filter has an orange componet added to the magenta to convert 4800K to 3200K. The FL-D assumes you are shooting on daylight-balanced stock and is mostly just magenta. The FL-D could therefore also be used to reduce green in a Warm White tube on tungsten stock. Or you can use a CC Magenta filter.

Since nowadays even Cool Whites vary in the amount of green, these filters won't correct perfectly but they get you in the ballpark. However, if you can't afford the stop loss, you might get away with a lighter CC Magenta filter instead of the FL-B or FL-D.
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#17 Jess Haas

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Posted 01 January 2008 - 04:02 PM

Kino tubes are high output tubes(or is it very high output? im not sure). This means that in a standard fluorescent fixture they will be under driven resulting in less light output and incorrect color balance. It should be about the same as running a 4ft tube in 2ft mode in a kino fixture. When under driving the bulbs they will appear more magenta than normal. It is possible to get high output fixtures but you will need to do a bit of research to find out what the output needs to be to match the kino bulbs.

If you want to get a fixture with a high frequency ballast you will most likely end up with a fixture designed for T8 bulbs. Kinos generally use T12 bulbs.

There are some very good fluorescent bulbs available for standard fixtures. Look for something with a CRI over 90 and a suitable color temperature and you should get good results. I recently used 20 hardware store T8 fixtures to light a green screen for a shoot with good results.

~Jess
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#18 Tim O'Connor

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Posted 01 January 2008 - 09:57 PM

Kino tubes are high output tubes(or is it very high output? im not sure). This means that in a standard fluorescent fixture they will be under driven resulting in less light output and incorrect color balance. It should be about the same as running a 4ft tube in 2ft mode in a kino fixture. When under driving the bulbs they will appear more magenta than normal. It is possible to get high output fixtures but you will need to do a bit of research to find out what the output needs to be to match the kino bulbs.

If you want to get a fixture with a high frequency ballast you will most likely end up with a fixture designed for T8 bulbs. Kinos generally use T12 bulbs.

There are some very good fluorescent bulbs available for standard fixtures. Look for something with a CRI over 90 and a suitable color temperature and you should get good results. I recently used 20 hardware store T8 fixtures to light a green screen for a shoot with good results.

~Jess


Cool, thanks.

I'm slowly building up my kit. I bought two Mole-Richardson Studio Juniors today for $225.00 for both which I'm pretty
excited about. I need to put Edisons on them and clean up some scratches but still a good deal I think.
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