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Old April 8th, 2008, 04:47 PM   #1
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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?
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Old April 8th, 2008, 05:01 PM   #2
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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/
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Old April 8th, 2008, 06:35 PM   #3
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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.
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Old April 8th, 2008, 08:34 PM   #4
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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.
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Old April 8th, 2008, 10:04 PM   #5
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Quote:
Originally Posted by Oliver Darden View Post
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.
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.

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I though you did that when you did a white balance.
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.

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He then says at the end "you need to switch the white balance on the camera so it thinks blue light is white light".
Exactly. He's setting the white balance for daylight so the camera will render daylight ("bluish" light) as white.

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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?
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"
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Old April 9th, 2008, 12:01 AM   #6
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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....

Last edited by Oliver Darden; April 9th, 2008 at 12:08 AM. Reason: oh ya
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Old April 9th, 2008, 12:52 AM   #7
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Originally Posted by Oliver Darden View Post
When I think white balance I think of putting a white / grey card in front of the camera and hitting the white balance button.
Yes, you can manually set the white balance in that manner, but frequently there are also presets for specific kinds of lighting.

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How can you have a preset on your camera for white balance when every lighting situation is different?
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.
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Old April 9th, 2008, 12:54 AM   #8
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-[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.
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Old April 9th, 2008, 03:04 AM   #9
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Originally Posted by David Garvin View Post
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.
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.
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Old April 9th, 2008, 06:04 PM   #10
 
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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.
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Old April 9th, 2008, 10:26 PM   #11
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Originally Posted by Oliver Darden View Post
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.
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.
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Old April 9th, 2008, 10:34 PM   #12
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Originally Posted by Jay Gladwell View Post
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.
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.
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Old April 10th, 2008, 01:57 AM   #13
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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.
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Old April 10th, 2008, 04:07 AM   #14
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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.
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Old April 10th, 2008, 07:51 AM   #15
 
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Originally Posted by David Garvin View Post
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.
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?
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