Fluorescent fixtures, Kino 3200k bulbs, and rf shielding..DIY kino?

[Nick Walters]

I've been looking into making some cheap fluo lights for some time, and was wondering if anyone can help me out, give opinions, or lead me away from making mistakes.

My general thoughts have been that Kinos are mostly made to cut down on RF, match certain lighting situations, and be durable/long lasting.

I am willing to sacrifice the last to have the first two, and have it cheap.

I was thinking of buying an off the shelf fluo fixture like this one:
http://www.lowes.com/lowes/lkn?action=productDetail&productId=293609-337-LOWES-2GR8LU&lpage=none

A few kino bulbs like these:
http://www.bhphotovideo.com/c/product/541869-REG/Kino_Flo_483_K32_True_Match_Fluorescent_Lamp.html

On shielding RF I was thinking of just shielding the ballast, as most info I've read has said that RF noise comes from the ballasts and fluo bulbs.....I'm guessing that Kino goes to great lengths to have bulbs that don't emit any nasty RF, which is the reason I'm thinking of using their bulbs.

To shield higher frequency RF I was thinking of using some faraday shielding....not sure what kind should be used, but I was thinking about some 3M 1245 copper tape

For low frequency RF signals I was thinking of either using some mu-metal sheet, or some mu-metal foil.

Basically I would put mu-metal around the ballast, solder on a wire to the mu-metal, tape over the mu-metal with the 3M 1245, solder a wire to the copper tape(all pieces), twist the wires coming off the copper and mu-metal together, and connect them to ground.....any left over 3M 1245 I would use to wrap the wiring going from the ballast to the lights(and ground them).


Then to top it all off I'd install an inline switch for easier use, some barn doors made from wire, cardboard, dowels, and tape, spray paint the barndoors and the fixture, install a baby plate, and mount her on a C-stand.

I think some switches could be easily installed as well so that you could turn on just two lights at a time.

A big question I suppose I have for anyone who knows anything about Kino's is : Can you put their T8 tubes in any T8 fixture? I'm worried that perhaps the voltages and such could be different for kino T8's versus regular vanilla T8's....heck I don't even know much about the T designations, so perhaps I'm asking a stupid question?


Oh and by my rough figures one 4 bank light would cost about $215. Of course one could forgoe the RF shielding and bring it to around $150....heck if you just wanted to go totally bare bones, i.e. no baby plate, barn doors, switches, or paint it'd only be about $110

I was even thinking of buying some 5500k bulbs as well, then I could have a light that could go both 3200 and 5500, for maximum flexibility, at about $285.

Oh, one last thing....and I don't reccomend anyone doing this...I was also going to open the balllast to ensure it is grounded, and grounded well.....without proper grounding any piece of equipment can start causing quite a bit of nasty RF...this is good to remember for all you folks using ground lifters on different pieces of equipment.


Any thoughts? Advice? Warnings?

 

[paulears]

My experience with flu fittings is that here in the UK (with our over the top electrical safety rules) the fixtures with pressed steel construction already have pretty good grounding with overlapping seals. Bonding is already in place, with lift off components like access lids bonded to the main unit. I've never had RF issues with these type of fittings, unlike the cheaper plastic fitting which can be a little 'leaky'. To the best of my knowledge, the tubes are just phosphor variants with more friendly colour temperature, at 3-4 times the cost of a conventional flu tube.

The troffer as a diffuser (not a term we use in the UK) requires the use of a ceiling fitting that may well have RF issues, being an installed product - if I've understood it properly - and these, if they are similar to UK ones are very flimsy and I'm not sure how they'd mount up as a freestanding one.

I think I'd like to maybe try some individual fittings, like this double one
http://cpc.farnell.com/eterna/d118/fluorescent-fitting-diff-2x58w/dp/LA02792
which has a defuser and is dirt cheap (UK price)

A few of these, side by side would be interesting to check for quality of light - and if good, then swapping to colour balanced tubes would be good. Price wise at a tenth the price of a commercial product - it could well be worth a punt?
EDIT - I'm thinking something like this

http://www.earsmedia.co.uk/flufitting.pdf

 

[Nick Walters]

I've done a little more digging with search and found some interesting stuff I might try...definitely with using coroplast sheeting and wire sleeves with copper in them :
http://www.dvxuser.com/V6/showthread.php?t=145518

Lots of really good info. I think I'm gonna depend alot on that thread and try to put together a video on putting a DIY Kino together....unrelated, but I also have an el-cheapo matte box video I still need to finish editing.

 

[pmark23]

Forget about RF -- it isn't a problem. I've built a few using the cheapest Chinese ballasts, and you have to put the microphone a mm away before you hear any buzz.

 

[Nick Walters]

I keep going back and forth on what I'm gonna do, but luckily while pokin around the basement here I found some T8 and T12 fixtures I'd forgotten about, and gutted them...so I have 4 32watt sound class A T8 ballasts now, and 4 T12 sound class A ballasts at 40w...I also found some wiring conduit layin' about, so now all I need is some coroplast, bulbs, reflectors, and some misc. mounting hardware. bad thing is that I didn't anticipate the bulk of all the various ballasts, so I'll prolly have to forgoe the shielding, and hope for the best.


I'm still thinkin of going with 3200k, as I've been lookin at some used 2k's that I might just purchase, and I'd like to match my lighting as much as possible as I'm first starting my kit. I figure one or two 4 banks with bulbs at 3200k, 2 2k's, and then a couple clamp lights with 85w 3200k CFL's should do me just fine at first.

One of my biggest problems at this point is finding T8 3200k bulbs...it seems I either have to go uncoated, pay out the nose for a bulb, or buy in bulk... the alternative is of course just buying T12, but I was hoping to use all my ballasts so that I had both a T8 and a T12 fixture, both with safety coated bulbs.

If anyone out there knows a decent source for T8 3200k bulbs that are saftey coated, please let me know. I'm also trying to figure out either where to buy a decent reflector, or make one....I might acctually give up and buy more kino brand stuff, as BH has their reflectors(although not in stock).

 

[Nick Walters]

Forget about RF -- it isn't a problem. I've built a few using the cheapest Chinese ballasts, and you have to put the microphone a mm away before you hear any buzz.

Thanks for the heads up...I was kinda worried about this at first...I guess I'll just ensure I properly ground, and make sure I do tests.

 

[Jim Brennan]

I've done this 2 ways. Both were cheap and effective.

1) I bought a couple of 4' Lights of America 1055SS fixtures at Lowe's. I don't think they carry them any more, but they are super quiet fixtures that take both T-8 and T-12 bulbs. They cost me less than 20 bucks a piece. I put in some T-8, daylight balanced bulbs from Home Depot that had around an 85 or 87 CRI. Then I put some conduit on the back to attach a maffer clamp so I could put it on a stand. No barn doors, and limited mobility. But my guess is that they cost me less than 50 bucks each in parts (including bulbs) and I have been using them for about 4 or 5 years now. I store and transport them in a hard shelled golf club case. 2 of them fit perfectly.

2) I took two 3" deep baking tins that were about 12"x16" (sorry I don't have exact measurements). Then I took some light gauge sheet metal and created a wall that extended from the handle of the pan on each side and over the pan about 2 inches before bending back to meet the bottom of the pan. This creates both a cavity for wiring, and also a second wall inside the pan to drill into and put sockets for CFLs. I bought some sockets for CFLs (Got mine from MattinSTL, but you can get something that works elsewhere). and put 3 on each side of the pan so that the bulbs look like they are laying flat in the pan instead of sticking out. This way you get more lit surface area exposed, and they store flat. I wired it with 2 switches so that I can turn each side on independently. I attached a yoke and a Smith Victor light stand adapter on the yoke so it will receive any standard light stand. I have used these regularly for about a year now. They work great and although they took a little longer to build (cost was about 50 bucks each as well), they are more portable and versatile than the 4' fixtures. I spray painted the outside black and nobody has ever said, "hey, is that a baking pan?"

 

[Nick Walters]

I've done this 2 ways. Both were cheap and effective.

1) I bought a couple of 4' Lights of America 1055SS fixtures at Lowe's. I don't think they carry them any more, but they are super quiet fixtures that take both T-8 and T-12 bulbs. They cost me less than 20 bucks a piece. I put in some T-8, daylight balanced bulbs from Home Depot that had around an 85 or 87 CRI. Then I put some conduit on the back to attach a maffer clamp so I could put it on a stand. No barn doors, and limited mobility. But my guess is that they cost me less than 50 bucks each in parts (including bulbs) and I have been using them for about 4 or 5 years now. I store and transport them in a hard shelled golf club case. 2 of them fit perfectly.

2) I took two 3" deep baking tins that were about 12"x16" (sorry I don't have exact measurements). Then I took some light gauge sheet metal and created a wall that extended from the handle of the pan on each side and over the pan about 2 inches before bending back to meet the bottom of the pan. This creates both a cavity for wiring, and also a second wall inside the pan to drill into and put sockets for CFLs. I bought some sockets for CFLs (Got mine from MattinSTL, but you can get something that works elsewhere). and put 3 on each side of the pan so that the bulbs look like they are laying flat in the pan instead of sticking out. This way you get more lit surface area exposed, and they store flat. I wired it with 2 switches so that I can turn each side on independently. I attached a yoke and a Smith Victor light stand adapter on the yoke so it will receive any standard light stand. I have used these regularly for about a year now. They work great and although they took a little longer to build (cost was about 50 bucks each as well), they are more portable and versatile than the 4' fixtures. I spray painted the outside black and nobody has ever said, "hey, is that a baking pan?"

GREAT tip on the golf case!!!

I saw the mattinstl post on the cake pan fixture, and I was actually thinking about doing exactly this(and maybe looking him up for some parts as I'm around St. Louis as well) and also some experimentation with LED lighting using this method and this stuff:
6 of these(they come in sets of two) : http://justpal-inc.amazonwebstore.com/One-Pair-1157-White-24-LED/M/B0017LBJGK.htm
6 of these : http://store.partsfortrucks.net/unso84.html
1 of these : http://webtronics.stores.yahoo.net/12vol150wats.html

I'm unsure what the color temp on the LED's are, so maybe I'll order a pair and sit with them in a dark room with my color temp. guage.

I figure about $130-$140 for ~150W of LED light....be in a pretty small package too.

On a side note...I wish the forum allowed short term searches...I've had to do a custom search onto this site from elsewhere, as it doesn't allow a search term as short as "LED".

 

[Nick Walters]

I've done this 2 ways. Both were cheap and effective.

1) I bought a couple of 4' Lights of America 1055SS fixtures at Lowe's. I don't think they carry them any more, but they are super quiet fixtures that take both T-8 and T-12 bulbs. They cost me less than 20 bucks a piece. I put in some T-8, daylight balanced bulbs from Home Depot that had around an 85 or 87 CRI. Then I put some conduit on the back to attach a maffer clamp so I could put it on a stand. No barn doors, and limited mobility. But my guess is that they cost me less than 50 bucks each in parts (including bulbs) and I have been using them for about 4 or 5 years now. I store and transport them in a hard shelled golf club case. 2 of them fit perfectly.

2) I took two 3" deep baking tins that were about 12"x16" (sorry I don't have exact measurements). Then I took some light gauge sheet metal and created a wall that extended from the handle of the pan on each side and over the pan about 2 inches before bending back to meet the bottom of the pan. This creates both a cavity for wiring, and also a second wall inside the pan to drill into and put sockets for CFLs. I bought some sockets for CFLs (Got mine from MattinSTL, but you can get something that works elsewhere). and put 3 on each side of the pan so that the bulbs look like they are laying flat in the pan instead of sticking out. This way you get more lit surface area exposed, and they store flat. I wired it with 2 switches so that I can turn each side on independently. I attached a yoke and a Smith Victor light stand adapter on the yoke so it will receive any standard light stand. I have used these regularly for about a year now. They work great and although they took a little longer to build (cost was about 50 bucks each as well), they are more portable and versatile than the 4' fixtures. I spray painted the outside black and nobody has ever said, "hey, is that a baking pan?"

I bet if you banged on the pans a bit to make them a little more parabolic you could gain more light output from the side facing the back of the pan.

 

[Jim Brennan]

I bet if you banged on the pans a bit to make them a little more parabolic you could gain more light output from the side facing the back of the pan.

Probably true. I put reflective tape inside, which helps. My impression of getting an effective parabolic shape is that the help is minimal outside of certain tolerances. Those are tolerances that hurt my head.

The main difference between Matt's design and mine is the direction of the bulbs. He set his up to be used with a softbox. Otherwise I took everything from him....then made it better :grin:

If he has any more of the sockets he sold me, I highly recommend them. First off, they have 2 threaded collars on the body of the fixture that allows them to be fastened to any surface that you can drill a hole through for the fixture, and adjust how far the fixture extends. They have simple connectivity and the bulbs screw in and out very smoothly. Matt is a stickler for good quality control. If he recommends something, you can take it to the bank.

 

[Nick Walters]

Probably true. I put reflective tape inside, which helps. My impression of getting an effective parabolic shape is that the help is minimal outside of certain tolerances. Those are tolerances that hurt my head.

The main difference between Matt's design and mine is the direction of the bulbs. He set his up to be used with a softbox. Otherwise I took everything from him....then made it better :grin:

If he has any more of the sockets he sold me, I highly recommend them. First off, they have 2 threaded collars on the body of the fixture that allows them to be fastened to any surface that you can drill a hole through for the fixture, and adjust how far the fixture extends. They have simple connectivity and the bulbs screw in and out very smoothly. Matt is a stickler for good quality control. If he recommends something, you can take it to the bank.

I don't know the math either, so maybe it isn't worth trying, but replacing the pan with a metal bowl and mounting them near the top(hopefully one with a straight lip at the top), could help reflect the backside of the fluo's better:

Sorry for the quick dirty MS paint picture, lol.

 

[Nick Walters]

Just got an E-mail back from the company that makes the 1157 LED lights, and they say the color temp is roughly 7k, so I don't think it would be good for mixing with many other lights....but the cost definitely gets my mind churning that LED's are starting to become a little less expensive, and could be used as primary lighting sometime in the future. At just around 90 cents(USD) a watt it's not so bad.