"daylight CFLs" look terrible! Is it the CFL or color?

[M. Gilden]

Hey guys-
I have a teacher friend who records theology lectures for youtube, and asked me to help him set up a cheap studio at home to make it look good. I originally set him up with a 5-tungsten lamp system (3 on him, 2 to blow out the white background), and they looked pretty good, but he says they get waaay too hot for the longer lectures. So he bought one of those multi-CFL soft box kits (I think Cowboy Studio?) with the "daylight full-spectrum" color bulbs, and a couple of those large 85watt oversized CFLs to put in the two fixures to blow out the background.

He asked me to come over and help him set up the camera to make it look good, but I can't believe how terrible the lighting is! I blamed the camera at first (VIXIA HF G30), but the truth is its a pretty nice little camera. My gear (GH2, Sony A7s) didn't really look much better. No matter how I tried to white balance, the lights made him look sickly with blue/green/grey overtones. I warmed it up as much as I could, but I still didn't like how it looked in camera. The tungsten lights really looked so much better, and were a cinch to white balance!

So the question is, not having a lot of experience with these CFL kits... is this normal? Is the problem the CFL technology, or is it the color? Would getting 2700k CFLs work better? Or should I tell him to ditch the whole CFL system alltogether?

Anyone have any opinions/insights to share?

 

[Alex H.]

Cheap CFLs are going to look terrible. Cowboy Studio may be okay for dirt-cheap camera support (even then, you get what you pay for) but I have not experienced any lighting from them that looked decent or functioned reliably, and the worst in my personal experience was their CFL softbox fixtures. You might get somewhat back to normal-ish with some 1/8 or even 1/4 minus green, but that's still not going to get you there.

 

[M. Gilden]

Thanks Alex. So would you say the problem is in the bulbs or the fixture? Surely the fixure doesn't need to be of high quality to look decent- it just needs to power the bulbs and hold a diffusing peice of cloth in place, which it does. Right? I'm trying to give this guy an expert opinion on what he should do, so would you recommend bulbs from another manufacturer? Or replace the whole danged thing?

 

[Michael Carter]

Well, a lot of cheap CFL and even biax can have oddball color casts. Some are yellow and require more of a violet gel setup. White balance only gets you close.

If you can, return those POS units for some 55w biax fixtures.

If not, and if you have a camera that shoots raw stills: set up a grayscale card or black, gray and white WB cards. Shoot a still under the CFLs.

Open it in camera raw and play with the color temp and tint sliders until you get even grays and whites. Eyedropper the cards and get the RGB values as close as possible to the same number (IE 25R25G25B, or 128r 130g 126b) the number itself isn't important, it will vary based on density - that all 3 numbers are very close is what gives you an even gray. (If those sliders are extreme, you're probably screwed).

Look at the color temp and tint sliders - that will tell you what you need in CTO or CTB. The "color" of the tint slider will show you an idea of minus green or +green. "A little bit" of magenta may equal to 1/4 minus green, etc.

Gel the fixture with you best guess, shoot again, and see how close you got to not needing tint and 5200-5500k.

I've also opened images as 5500k and played with "photo filter" adjustment layers to get an idea of what gels are needed. But work with grays and whites and look for even RGB values vs. trying to dial in skin tones.

Or just try 1/2 CTO and 1/8 minus green, which I find fixes a lot of stuff… but I have CFLs that need minus green and CTB, which is bizarre...

 

[M. Gilden]

Well, a lot of cheap CFL and even biax can have oddball color casts. Some are yellow and require more of a violet gel setup. White balance only gets you close.

If you can, return those POS units for some 55w biax fixtures.

He's had them for months, using it to light himself when recording via webcam. He can't return it at this point, only try other options.
I got involved because he wants to up the production value (hence the $1,200 Vixia cam purchase), but I doubt he's willing to spend thousands more on flourescent biax fixtures after that. You don't think better brand or color bulbs in this fixtures would help?

 

[nyvz]

How was he whitebalancing? 5600k/daylight Preset or custom white card? If there is a color cast or unexpected color temperature to the bulbs, custom white balancing could help fix it, but if its just bad CRI that is particularly bad in skin-colored tones it may not be easily fixable.

I wouldn't rule out all fluorescents or all CFLs as I've had luck with some of them, but you really have to test them first since they all have limitations in color relative to tungsten.

I wouldn't expect 2700/3200k CFLs to be any better unless the daylight CFLs are particularly horrible and the 3200k CFLs happen to have a better spec, but normally I find 3200k to be worse. Usually the daylight CFLs are more color accurate and have less green-magenta cast in my experience.

 

[mcbob]

Anybody going that route with lighting should try CREE LED bulbs, either daylight or 'soft white' tungsten balanced... they max out at 100W equivalent', but they're pretty darned good for a household LED bulb and aren't half as fragile or ugly as most CLFs. I keep a few around for re-lamping practicals that may wind up in frame to the appropriate color/intensity (they're dimmable).

 

[M. Gilden]

How was he whitebalancing? 5600k/daylight Preset or custom white card? If there is a color cast or unexpected color temperature to the bulbs, custom white balancing could help fix it, but if its just bad CRI that is particularly bad in skin-colored tones it may not be easily fixable.

I wouldn't rule out all fluorescents or all CFLs as I've had luck with some of them, but you really have to test them first since they all have limitations in color relative to tungsten.

I wouldn't expect 2700/3200k CFLs to be any better unless the daylight CFLs are particularly horrible and the 3200k CFLs happen to have a better spec, but normally I find 3200k to be worse. Usually the daylight CFLs are more color accurate and have less green-magenta cast in my experience.

I was doing the white balance for him, he asked me to set it up. I did a custom WB pointing the camera at his white shirt (turning down the exposure first so it was grey). Then I tried dialing it in manually. Did not like what I was seeing either way.

Anybody going that route with lighting should try CREE LED bulbs, either daylight or 'soft white' tungsten balanced... they max out at 100W equivalent', but they're pretty darned good for a household LED bulb and aren't half as fragile or ugly as most CLFs. I keep a few around for re-lamping practicals that may wind up in frame to the appropriate color/intensity (they're dimmable).

Nice- the fixtures this guy is using are 6 light bulb sockets inside a cloth soft box. The CFLs in there now are probably 40-60 watt equivelent, x 6 = 240-360 watt equivelants. If he picks up some LED 100W equivs, that sounds like a nice 600W if the color is actually somthing easier for me to work with! Thing is, if each bulb is $10, that's $60 per unit, and there are 3 of them ($180). That's not bad, to be honest.... but then he'll still need lights behind him to blow out the background... maybe he can just use those 500W tungsten bulbs I originally set him up with (impact light stands from B&H) for that. IF its behind him, perhaps the heat won't be so bad?

 

[Bruce Watson]

I did a custom WB pointing the camera at his white shirt (turning down the exposure first so it was grey).

Don't. Use an 18% gray calibration target; you are trying to calibrate your camera to your lights, you need a reference. The calibration target is that reference. A white shirt won't cut it -- you don't know what color cast it might have, what metameric properties it might have, you don't know how much of his skin might show though, and it's almost certainly not flat, and therefore not lit evenly. No wonder your manual white balance attempt failed.

For reference, use the gray side (there's good reasons to not use the white), have him hold the target in front of his face so that the target is lit just like his face will be, and zoom in to completely fill the viewfinder with the target. Then do the manual white balance. Then put the target back into its protective cover and put it away (don't just lay it down where it can get dirty), zoom back out, etc.

Nice- the fixtures this guy is using are 6 light bulb sockets inside a cloth soft box.

Use cine bulbs. KinoFlo makes some. Westcott does. Look around, they aren't difficult to find. You can even get reasonable bulbs from BlueMax. I use these in practicals. And in my living room. :thumbsup: These are all typically six or seven phosphor bulbs (CRI in the 90s), and have a much nicer color spectrum with a considerably reduced green spike. Much easier to get a good manual white balance with.

Good light sources combined with good white balance technique will probably cure this problem for the most part.

 

[Michael Carter]

... I doubt he's willing to spend thousands more on flourescent biax fixtures after that. You don't think better brand or color bulbs in this fixtures would help?

You can get a 4-bank 55w Biax for $200 or less these days. if you want trumatch Kino bulbs, that's another $100 or so for four.

But I get it that he's got the hardware. Some good advice has been posted here, and take a look at my post above regarding dialing in gels. It's actually kind of geeky fun, and usually when testing, you learn more than you set out to.

 

[M. Gilden]

Don't. Use an 18% gray calibration target; you are trying to calibrate your camera to your lights, you need a reference. The calibration target is that reference. A white shirt won't cut it -- you don't know what color cast it might have, what metameric properties it might have, you don't know how much of his skin might show though, and it's almost certainly not flat, and therefore not lit evenly. No wonder your manual white balance attempt failed.

For reference, use the gray side (there's good reasons to not use the white), have him hold the target in front of his face so that the target is lit just like his face will be, and zoom in to completely fill the viewfinder with the target. Then do the manual white balance. Then put the target back into its protective cover and put it away (don't just lay it down where it can get dirty), zoom back out, etc.



Use cine bulbs. KinoFlo makes some. Westcott does. Look around, they aren't difficult to find. You can even get reasonable bulbs from BlueMax. I use these in practicals. And in my living room. :thumbsup: These are all typically six or seven phosphor bulbs (CRI in the 90s), and have a much nicer color spectrum with a considerably reduced green spike. Much easier to get a good manual white balance with.

Good light sources combined with good white balance technique will probably cure this problem for the most part.

Some good advice here. I have 18% grey cards in my gear bag for this reason, but I was setting up HIS studio, and didn't have my gear. I know grey cards will be much more accurate than white, but I was just trying to work with what I had there and show him what to do. In my experience, when I don't have access to a grey card, using something white gets me most of the way there. But it doesn't matter- even dialing in manual kelvin values and scrolling through the available range, I wasn't able to find something that didn't make him look sickly.

Maybe I'll look into BlueMax for him.

 

[Bruce Watson]

...even dialing in manual kelvin values and scrolling through the available range, I wasn't able to find something that didn't make him look sickly.

That's because dialing in a Kelvin number is only about the orange-blue axis. The trouble with fluorescent lighting is the magneta-green axis, and your Kelvin dial has no effect on it. To effect the magenta-green axis, you have to do a manual white balance (as opposed to dialing in a K number) and let the camera do its thing with the gray card. You can't tweak it after because you'll lose that correction on the magenta-green axis.

 

[omnikron]

That's because dialing in a Kelvin number is only about the orange-blue axis. The trouble with fluorescent lighting is the magneta-green axis, and your Kelvin dial has no effect on it. To effect the magenta-green axis, you have to do a manual white balance (as opposed to dialing in a K number) and let the camera do its thing with the gray card. You can't tweak it after because you'll lose that correction on the magenta-green axis.

Bruce, I've never heard this before. I would imagine this would depend on the camera. Are you aware of this being a near universal truth? For example, Black Magic cameras (or at least the BMPCC) doesn't allow a manual white balance. You can only select pre-defined Kelvin temps. I shoot with the C100, BMPCC, and GH4.

 

[Moseph]

There is no reason for kelvin temperature on a manual white balance to affect how green or magenta the picture is. Warm vs cool and green vs magenta are two totally different properties that need to be adjusted independently. To get the hue right under lighting that is somewhere off of the "planck locus" in color, you have to pull an auto white balance off a card, use filters / do the color correction in camera, or use CC gels on the lighting. I'm not very up to speed on most cameras these days but I know the Alexa lets you color correct in camera, I'd imagine many others do as well.

 

[Bruce Watson]

Bruce, I've never heard this before. I would imagine this would depend on the camera. Are you aware of this being a near universal truth?

Universal Truth? I can't imagine such a thing.

Manual white balance that corrected for other than just the orange-blue axis came to low end cameras because consumers tend to shoot in available light, and the available light in most places is crappy fluorescent. If camera companies wanted to sell cameras, they had to give the consumers a way to make decent looking vids under highly variable and suspect lighting. No choice. Do it or watch the consumers buy from competitors.

It has trickled up (or down, IDK), especially into ENG cameras, because news shooters have some of the same "we have to shoot in whatever light they use at the court house" kind of problem.

The last to get hit, if they do, is the pro cinema cameras. Because those manufacturers expect their cameras to be used with cinema lighting. IOW, they don't expect to have to deal much with color casts, and they expect you to modify the light if you need to, using gels to change color as needed.

I'm just saying that today's cheap handy-cams can usually do an amazing manual white balance (why do they call it that? It's really a gray balance, or if you want, a neutral axis balance) that'll give you excellent skin tones under seriously bad lighting. As the cameras get better and more expensive, some to better (more axes) and some do worse. It seems to depend on the niche their manufacturers are aiming them toward.

 

[omnikron]

Universal Truth? I can't imagine such a thing.

Manual white balance that corrected for other than just the orange-blue axis came to low end cameras because consumers tend to shoot in available light, and the available light in most places is crappy fluorescent. If camera companies wanted to sell cameras, they had to give the consumers a way to make decent looking vids under highly variable and suspect lighting. No choice. Do it or watch the consumers buy from competitors.

It has trickled up (or down, IDK), especially into ENG cameras, because news shooters have some of the same "we have to shoot in whatever light they use at the court house" kind of problem.

The last to get hit, if they do, is the pro cinema cameras. Because those manufacturers expect their cameras to be used with cinema lighting. IOW, they don't expect to have to deal much with color casts, and they expect you to modify the light if you need to, using gels to change color as needed.

I'm just saying that today's cheap handy-cams can usually do an amazing manual white balance (why do they call it that? It's really a gray balance, or if you want, a neutral axis balance) that'll give you excellent skin tones under seriously bad lighting. As the cameras get better and more expensive, some to better (more axes) and some do worse. It seems to depend on the niche their manufacturers are aiming them toward.

Interesting. I know a lot of cameras allow you to adjust the color axis in-camera. I think for me, what's alarming is that you are saying when you do a auto(or manual? Whatever you want to call it) white balance with a grey card, the camera is not only affecting the yellow/blue axis but also the magenta/green axis. The problem is all the cameras I've used display the kelvin temperature of the white balance it selects but never a +/- green/magenta tint. So that's what makes me surprised about your comment. I had no idea it would affect green/magenta with a white balance using a grey card, because the camera never gives me any indication that that is a parameter is it adjusting. I guess I just need to throw some green or magenta light on a card and LOOK.

 

[Moseph]

The camera telling you what kelvin temperature it's selected from pulling an auto white balance is a feature I've never actually come across, but if it's the case that many of them do, I'm not too surprised that they don't report what color correction it's performed. My thinking is that it's not something you'll want to tweak the same way you might for the color temp, so letting you know what it's done about the Y axis doesn't help you much unless you want to throw the right CC gel on your lights.

 

[Tom Roper]

I used the cheap interview 3 light CFL softbox kit with egg crates from Cowboy Video for an out of town shoot. I thought it worked fine. I white balanced on a white card, and did only the mildest grade, thought it looked good. I excluded other light sources and moved the lights in close for soft effect. So I dunno, maybe the CRI was bad, but the client was happy with it. You tell me. You can see the 2 clips here at http://internationalgiving.net

 

[Michael Carter]

My hard-learned experience:

Balance to a calibrated gray card. You can get lucky with white, you can cut your exposure so the white is actually in the high-gray range, but a for-real gray card is much more guaranteed. SO MANY WHITES have "blueing" to make them seem whiter (fabrics, printer paper, etc) - but, often that will give you a subtle but pleasingly warm WB. Maybe not accurate, but often nice. I sometimes WB through a scrap of 1/8 CTB gel for that reason… though 1/8 CTB seems to be hard to find these days. Hell, in a pinch Ive balanced off white curtains, white chair pads, put a white bar napkin over the lens. But a gray card will get you closer to accurate color. If you've got multiple cameras on a shoot, it's even more important.

Selecting a K temp? I've had the same results. Not as accurate as a white balance that addresses magenta-green tint. Play with the temp and tint sliders in a camera raw file and you'll see how important this is.

I can't speak for every camera out there, but in my experience (maybe a dozen camera models in the last five years with enough hours to be "second nature" with them) manual balance is far more accurate than the K controls (if they're even there). I only use the kelvin controls if I want a shot warmer or cooler than what I'm seeing.

The fact that BMC, etc. don't have manual WB controls has no bearing on what goes into manual white balance. It's a mixture of kelvin and magenta/green tint, and the tint is often vital. I have no data or scientific papers to back that up, but in my experience, it's a universal truth.