Izzy Video Lighting question
 

What does Izzy mean when he says he is "balancing for sunlight and balancing for tungsten light on the camera"? He says "I need to adjust the white balance so its matched with the sunlight". I though you did that when you did a white balance.

http://www.izzyvideo.com/2008/03/10/...light-sources/

He then says at the end "you need to switch the white balance on the camera so it thinks blue light is white light".

I understand balancing for different light sources but I don't know what he means about changing the setting on the camera. Is there a setting that you have to put it to daylight, indoor, outdoor, tungsten etc THEN do your white balance?

Tungsten lights are ~3200K, sunlight is more like ~5400k and up. If you whitebalance your camera under tungsten lights, things will look blue in sunlight. When you whitebalance a camera you actually set it up for the color temperatue of the lightsource.

When you mix lightsources, like sunlight through a window and tungsten lights inside, you can get in trouble as there will be more than one, resulting in red/blue casts. So you balance the light using gels. Look up CTO and CTB in google to get more info on these.

Or you can use 5400k HMI lights which match better with sunlight.

George/

Thanks for the reply George but like I said I understand white balancing and color temperatures. My question was about the quotes below and the difference between doing a setting on your camera and white balancing.

"you need to switch the white balance on the camera so it thinks blue light is white light".

I usually first get all my lights balanced by putting a 1/4 blue gel on all my Arri lights to give it more of a sunlight look (white / blue) and then I do a white balance.

Some pro cameras have a filter wheel in the optical path that integrates perhaps 2 different Neutral Density filters with 5600K filters, a plain 5600K, and also have a 3200K filter.

Then, you also do the electronic white balance that you're familiar with. And perhaps paint it a little warmer or colder, depending on the camera.

I don't know if this is what Izzy is talking about. This was fairly common practice several years ago, long before consumer and prosumer video cameras.

I haven't watched the video, but those quotes don't seem confusing at all. My guess is that he means exactly what he's saying. He is balancing to sunlight or tungsten light on the camera. He is balancing the color temperature settings on the camera so it is balanced to either sunlight or tungsten light. He is adjusting the white balance on the camera so it's balanced to sunlight. He is setting the white balance on the camera so it's set to 5600-degrees Kelvin. All of those sentences are saying the same thing.

That's what he is doing. He's setting the white balance on the camera. He's white balancing to a specific color of light (daylight or tungsten) so white objects will look white. He's setting the white balance.

Exactly. He's setting the white balance for daylight so the camera will render daylight ("bluish" light) as white.

It sounds like he's setting a preset on the camera so it's white balanced to the color temperature of the lighting. That IS the white balance, he's not doing that and THEN setting the white balance, he IS setting the white balance.

Your last question there can be rephrased as "Does he set the white balance and THEN do a white balance?" and the answer would be "No, he's setting the whitebalance on the camera to whatever light source he's using. Therefore it IS whitebalanced and there would be no reason to white balance it again"

When I think white balance I think of putting a white / grey card in front of the camera and hitting the white balance button. It then flashes and THAT is what tells the camera what is white. How can you have a preset on your camera for white balance when every lighting situation is different?

On my XL1s there is a gain and a white balance knob. On the white balance knob their is automatic white balance which sucks and the rest are 3 presets you can save, but there again how can you have a preset when light changes?

SO he probably went outside, took a white balance and set a preset to "daylight". And then did something similar indoors and he uses that one for indoors....

Yes, you can manually set the white balance in that manner, but frequently there are also presets for specific kinds of lighting.

Through the magic of film lighting! :) There's a reason that people use professional film lights to light sets and locations and not just any lightbulb they find lying around. That reason is that those professional lights are purposely color balanced to a specific color temperature. For tungsten lighting it's 3200-degrees Kelvin. If you're shooting with HMIs, it's 5600.

If you're lighting your scene with these lights, you know what the color temperature is. If you know what your color temperature is and your camera has a preset for that specific color temperature, you simply set the camera for that color temperature and you're set.

Think about it this way. In the film world, there is no "white balance" in the sense that you're thinking of it. You either buy tungsten balanced film or daylight balanced film. Each type of film stock is color balanced to a specific temperature. You might ask "How can you have a filmstock that's only balanced to a single color temperature when every lighting situation is different?" and the answer is exactly the same. The reason you can get accurate color rendition on film (where there is no "white balance" to be set electronically) is because professional lights are made to provide a specific color temperature and once you know what that is, you simply use the film that matches your lights. With the video camera, you simply use the preset that matches your lights.

-[QUOTE=Oliver Darden;856809]When I think white balance I think of
-putting a white / grey card in front of the camera and hitting the white
-balance button. It then flashes and THAT is what tells the camera what is
-white. How can you have a preset on your camera for white balance when
-every lighting situation is different?

Well nearly all fully professional cameras have precisely that. Presets that are factory calibrated to proper color exposure at 3200 kelvin using that filter and 5600 kelvin using that filter.

Among many reasons they are useful is if you have a scene that's primarily lit with a single type of source, but has an element (a small window perhaps in an otherwise tungsten lit scene) that could throw off the overall color reading if you simply white balanced on the scene as is.

Same as an office scene with large windows, but a strong desk lamp at 3200k.


-On my XL1s there is a gain and a white balance knob. On the white balance -knob their is automatic white balance which sucks and the rest are 3 --
-presets you can save, but there again how can you have a preset when
-light changes?

On prosumer class cameras such as you're describing, you may not like the white balance results from the presets. But extrapolating that to believe that ALL auto white balance, or ALL presets for that matter work equally poorly (if that's even accurate, I don't know never having shot with an XL-1) is pretty poor reasoning.

For example, the professional auto-tracing white balance on many of the pro level cameras I've used have been truely excellent. But that's on cameras where the LENS costs as much as an XL-1.

That makes sense, thanks for that explanation David. I guess it all depends on what your using, I use MiniDV so I guess for me it's advantageous to set my white balance (with a card) for every application. Izzy in that video is also using a MiniDV and mixed light sources, so it threw me off when he says he will set his white balance on the camera.

Izzy is mistaken. Sun light isn't blue, it's white. First, any blue comes from the blue sky, acting as a giant blue bounce card.

Second, sun light will only appear blue to your camera (excluding early morning and late afternoon) because it's been white balanced for tungsten, or any other source less than 5600 Kelvin. Therefore it "looks" blue, but in reality it isn't.

In order for sun light to be blue, it would have to be closer to 10,000 Kelvin.

One other thing to note is that I am speaking in generalities and the reality is that you will find a tungsten bulb isn't ALWAYS 3200-degrees Kelvin any more than an HMI is exactly 5600-degrees. The age of the bulbs, power supply issues and all kinds of other things come into play.

Additionally you should also keep in mind that film almost always goes through a grading process where the colors are adjusted before the final image is presented. Therefore the subtle differences in color (which would be analagous to being 'off' with your white balance) aren't necessarily ever seen by anybody but the colorist who is fixing those color issues. With Dv, on the other hand, the tape you pull out of the camera is going to show you those color discrepancies.

While technically you may be correct, our perception of color is relative and it is not uncommon for 5600K to be described as "blue" because it's bluER than tungsten lighting and because when your eyes become accustom to a lower color terperature like 3200K, 5600 does look blue to your eye, not just your camera.

So now that I have a lesson in light temperatures... lol

Basically working in a digital format it is safe to say I should do a white balance (with a white / grey card in front of the camera) before every shoot? Thats assuming I have matched all the lights (as best as I can) to the same temperature.

One of the things I like the most about the Sony V1 is the ability to dial in color temperature in 500Kelvin increments. It also has great color in auto unlike many previous cameras. I set the mired shift (green/magenta) and color temperature to taste and it is essentially what you see is what you get. I have displayed footage on a couple of LCDs and a couple of high-end plasma screens and the view finder is close enough. Setting white balance with cards is fine when the light is controlled, but event video can have rapidly changing environments. I also like to be able to slant the color to my mood just a bit to warm things up or cool it down depending on the circumstances. Try getting a white balance with a white card when you are trying to shoot a scene with warm streetlights and a daylight fake moonlight. Try getting your white balance when you are trying to fake sunset with studio lights and you will want a camera that can dial in a color temperature.

Sorry, Dave, I have to disagree. Direct sun light has never looked blue, and I've been in the business of making images for nearly forty years.

As I explained previously, any blue you may perceive is coming from the blue in the sky, not the sun light.

Let me ask you... On a clear, sunny day, what color are the shadows?

I'm not talking about the sun. I'm not talking about a clear sunny day or a cloudy day or a rainy day or dusk or dawn. I'm not talking about anything that involves the blue sky at all. I'm talking about 5600K and how that 'appears' to you when you have been working under the very common lighting sources with a lower color temperature. And if you work on a film set with tungsten lighting all day and then you turn on an HMI, it does indeed look blue to your eyes. NOT because there is "blue in the sky" but because your eyes and brain have "white balanced" to the warmer light sources.

You can insist that your eyes and brain work completely differently and that they don't adjust to the color temperature of 3200K and that you never ever ever perceive 3200K as "white" and I won't argue with you, but I'll tell you that you are one unique individual.

But we were talking about the sun, Dave. Izzy said sun light was blue. It isn't. Period.

It may appear that way to a camera that has been white balanced to 3600K, but that does not alter the actual color of the light, regardless of the source. Light at 5600K is white, not blue, regardless of it source. To say otherwise, like Izzy did, is incorrect and misleading.

Thanks for the info Marcus, seems I need to think about this on my next camera purchase. I have a choice to either get the latest and greatest HD camera or I have an opportunity to buy a really nice 16mm. I'm really not sure what I'm going to do. I love being able to shoot and come home and edit. With the 16mm I am going into a new world and I'm not sure if I am ready for $150 for 12mins. =)

Whatever I do I will look for these features as my xl1s does not offer anything like what your talking about.

Oliver, I think you will most likely be happy with a modern HD camera as a replacement for your XL1s. Your camera has a lot of shortcomings mainly due to it's CCDs. A camera with greater sensitivity and resolution will make a huge difference in your video. Newer cameras also have more features that allow image adjustment to your style. I like the results from film but I see it rapidly becoming a nostalgic format. In many ways, HD has equaled film and its workflow is far superior. Of course, cost is a huge factor against film.

Regarding the color of the sun, color temperatures, and the human eye/brain processing of light:

There is no White. White is simply how we perceive electromagnetic radiation that activates our three color sensors somewhat evenly. If all three cones are stimulated simultaneously, our brains label it as white. Whoever said that the sun is not blue is absolutely wrong. The sun has a great deal of high frequency emissions that are within and above our blue receptors. Where do you think the blue in the sky comes from? Is the sky blue? No, the sky is simply blue because the atmosphere has scattered and filtered sunlight. Compared to tungsten light, the sun has a huge amount of blue.

Yes, our brains perform the equivalent of an automatic white balance for us. Working with video we must understand how light works if we want to have ultimate control of our images. We must understand how people perceive light in contrast to what is being emitted. White balance is one example and moonlight is another. We perceive moonlight as "grey" because our color receptors are less sensitive than our colorless receptors. It is harder to see color in dim light so we get a feeling of "grey" light even though there is a rather broad spectrum of light bouncing off the moon.

So the question is....when will they make a camera that will auto balance to light like our eyes!?

Thanks again Marcus, your very informative.

If what you mean is a camera that auto-balances to a single color temperature, nearly all professional cameras do that just fine.

(Sony calls it "auto tracing white balance" - but other manufacturer's cameras do the same thing)

If, however, you mean look at a situation where there's mixed lighting and the camera can resolve all of it so that each each separate area of the scene looks "right" that takes a little more specialized processing.

That kind of processing currently requires a pair of eyes with a human brain attached.

so ill keep my eyes open for a camera with a brain included...cool, thanks.