Best daylight fluorescent bulbs
 

I put together a couple DIY Kinos, which I know have been discussed here, but I'm wondering what the best daylight bulbs available are. I found Philips 6500K bulbs at Home Depot (my fixture takes 48" T8 bulbs) that seem decent, but I remember hearing somewhere that there are higher quality daylight balanced fluorescent bulbs available--anyone have any thoughts?

The problem with flourescents is that some phosphors give a discontinuous spectrum --- some of the colors in the spectrum just aren't present. Some others have their spectra out of balance, so that some colors predominate ---- like too much green, too little red. Natural spectrum lamps purport to have a full range of colors in proper balance. Verilux is one manufacturer you might investigate. . Or this:
The Sunwave® full spectrum fluorescent light tubes are the most correct Full Spectrum Light tubes available in the world.

Disclaimer: haven't used either product. I used to buy full-spectrum lamps for a print-retouching and edit station at work, and they worked well. But that brand appears to be discontinued. However, the basic idea is to find a lamp that has the necessary colors in proper balance.

I use these but they're T12s -- assume they make a T8 version as well.

Shop SYLVANIA 10-Pack 40-Watt Commercial Fluorescents at Lowes.com

Edit: Yep, they do: http://www.1000bulbs.com/category/f3...rescent-tubes/

I use 5000K because it matches the other lights we use in the studio -- a bunch of fluoro softboxes that are 5100.

As you can see, the higher qualtiy bulbs are much more expensive -- up to $20 each compared to a little over a buck apiece for hardware store versions. But the premium ones have a CRI in the mid 90s, while the cheapos I use are in the low 80s.

I have been using ONLY Kino daylight and tungsten tubes in my homemade Diva 200s for four years now. Very accurate, consistent color and reasonable cost. Why fool with unknown quantity Home Depot bulbs? I don't get it, the Kino tubes are not that much more.

Dan

(double post)

That's what I'm looking for--accurate, consistent color. I didn't know Kino made tubes--just found them:
Kino Flo True Match Lamps

The Kino lamps are about 5 times more expensive, but that's well worth it for cleaner color. I wonder if there are any issues using these with cheap fixtures?

ETA:

There seem to be conflicting reports on whether you can get good results with non-Kino lamps or not. Some folks are saying hardware store tubes are fine, as long as the CRI is high and they're the right color temperature. I'll shoot some tests and report back. A couple threads:
http://www.cinematography.com/index.php?showtopic=28098
http://www.cinematography.net/edited...scentLamps.htm

Also, this: "Kino Flo bulbs have a CRI of 95. Anything below that has an ugly green spike that has to be gelled out..." from this thread:
http://forums.creativecow.net/thread/54/857002

Here are some tubes with very high CRI ratings, and a range of color temperatures:
http://www.topbulb.com/find/t8_fluorescent_lamps.asp

high CRI fluorescent bulbs
 

Look up the bulbs by Blue Max. Mostly fairly high CRI bulbs. Not really aimed at cinema, but might do the job.

The Philips TL950 gets good reviews.

The GTI bulbs are dynamite -- seven phosphor wonders. Expensive, but pretty darn good.

GE has a line of SHOWBIZ cinema bulbs. These are aimed directly at the cinema market. Lot of these show up in various "flo" fixtures.

Many of the above are available in bi-pin or biax configurations.

But can you work any of these without using a minus green gel? IDK. Claims are just clams. I have yet to find any experienced lighting people to tell me that. I'd love a fluorescent tube that didn't need to be gelled. But so would everyone else, so I'm sure if there were such a beast the manufacturer would be, um, less then shy about touting them. ;-)

The Kino lamps don't require minus green, do they? Thanks for the links.

These are all really great links and articles. Very educational.

We're dealing with many of these same issues. I think if you're only building a fixture or two there's no doubt that the price difference for the topnotch Kinos is negligible. We're re-tubing an entire building so paying ten times as much per tube can be a little daunting. With our cams we can dial in the exact WB color temp so using the cheap $3 5000K Sylvanias works fine for us and the color looks very nice.

One thing I noted in one of the articles is that the very high output Kinos may not put out their full potential when put into cheap hardware store fixtures with regular ballasts, and therefore the color and CRI would change. Worth noting. Another point that I've seen mentioned more than once is that small differences in CRI -- say from 90 to 92 --- aren't really significant.

All fluorescent bulbs create spikes in their output. Tis the nature of the beast. Look at the spectral power distribution curves for any given bulb. There's typically a spike for every phosphor used in the bulb. This includes the high CRI bulbs of course.

The real question is -- will it show up on film/video? Some say yes, some say no. I'm still looking for a definitive answer to that.

Considering Kino invented using fluorescent tubes for video, they spend a tremendous amount of time and money engineering their tubes to work well for film and video. My homemade Diva 200s use a better ballast than real Kinos, my ballasts alone cost about $120.00 ea. and operate at 30Khz. I have been using the same Kino daylight tubes with them since I built them, 2005. So they have been going for five years. Not a bad deal, I think I paid $22.00 each for them (55 watt Biax).

That said, I tried using Kino tungsten tubes in my POS Fotodiox Kino knock off and they burned out quickly. I would suspect that a cheap light like a Fotodiox has a crappy ballast that does not work well with the Kino tubes. Not only did the tubes short out in the Fotodiox, when the light shorted out, it actually fried the ballast in the light too, smoke came out from the light.

Not sure if I would use Kino tubes in a cheap fixture, but if you have high quality ballasts like a Kino, Coollights, Mole or the like, the Kino tubes work well. I don't feel that it is essential to use the Kino tubes to do a whole building, you are right, that would end up being pretty costly. With fluoros, all that matters is consistency. If all you see in your shots are just all of your tubes, as long as the ballasts aren't sick or full of flickering, that is all that matters. That's why they include manual WB buttons on cameras.

Dan Brockett

Well...just a minute.... (donning my flame retardant suit)

I use 23w and 42w home warehouse bulbs all the time...(actually...several varieties are made by Verilux..."full spectrum" is what they print on the box at least) I have a bunch of little Edison screw in fixtures that go on a light stand peg...they seem to work fine.

I almost always shoot at 23.976...no flicker...I always test them.

I don't have charts for the bulbs that show me the spectral properties, but the camera sees the light from the bulbs as 6500 or 5500 (depending on the bulb/manufacturer, etc.) and color correcting shots lit with the daylight hardware store bulbs is a much more flexible process than working with tungsten-lit scenes. The fluorescents may have a green spike, but relative to tungsten my experience has been very positive. I seem to have far more "palette" with the CFL daylight consumer "full spectrum" (per the box of course...) bulbs than I ever had with professional tungsten.

Also...as with Kinos, HMIs etc., most video cameras balanced to daylight don't have to gain up the blue channel as much as they would for tungsten color balance, which reduces noise introduced at that stage.

Not to mention...I can now work with daylight when I'm shooting interiors with windows and limited power resources, which cuts out set up time treating or blocking windows to light with tungsten (which is no bargain for power draw anyway).

I haven't found a CFL-based PAR light to replace a 1200w HMI yet, but for smaller areas and fill/bounce applications, etc, I suspect a head with four 42w CFLs throws far more light than most who haven't tried it would guess...

Anyway...I'm not usually an advocate for utilizing non-pro gear for pro work, but I've done enough small set and interview shots with these screw-in CFLs now to feel fairly confident in them and the heat they don't throw and the power they don't consume combined with the standard indoor electrical breakers I don't have to worry about tripping...are a nice bonus.

I'm not selling all my lighting gear and switching to hardware store gear BTW...it's just another option I now have that I didn't have before.

I spent a couple of days producing data and footage for a series of lighting lectures and came up with the following...

The KinoFlo daylight tubes were the most accurate on the colormeter and looked the most "natural" on the screen (tests done with a Panasonic HPX 3700 in HD on preset) If anything they had a slight tendency to magenta and looked ever so slightly better on pale skintones with an 1/8 plusgreen gel. However, this is really anal nitpicking and in practice I can't see anyone noticing it.

Closely followed by Osram Studioline daylight tubes.

All the rest, Dulux and Osram 956 and 950 tubes all showed a green spike. The 800 series tubes were virtually unusable for HD video, even with full minus green gel.

One thing which became very noticeable was that the tubes, especially the Kinos, needed good ventilation as they all went towards green if they got warm. Out of the units, the cheap Kino-copies and Chinese fittings were the worst offenders. The KinoFlo and Ianiro ICE units gave the best results. All the lamps moved slightly towards magenta when dimmed.

I didn't test the lamps for long, so I can't say how the Kinos lasted in other units but I've still got my original Kino tubes in a Divalight which is used each day, every day for about three years now.

Edit: Oh yeah, and all the lamps took at least a minute or so to "settle" at a constant colour temperature..

Thanks folks, this thread has been very helpful.

Shoot a scene with regular fluorescents. If it looks okay to you, you've got your answer. I hate overthinking things.

Incidentally, my dad's name is Bruce Watson, and it makes me do a doubletake everytime you post. :-)