New Indie Film Tech Tip: White Balance at DVinfo.net

Scott Spears · November 19th, 2005, 09:20 AM

Hey Folks,

I finally got around to making a new Indie Film Tech Tip on White Balance. (I've shot 6 features this year so free time has been tight.) This tip shows you the basics of how to use the White Balance feature on your camera to create different looks for your projects. It's a Windows Media file and runs around 3 min. and 14 sec.

Watch and enjoy.

http://www.scottspears.net/filmmakpg3.html

Scott

Glenn Chan · November 19th, 2005, 04:05 PM

As I argue in this thread http://www.dvinfo.net/conf/showthread.php?t=53844, tricking a video camera's white balance may not produce the effect you thought you had. Your eye sort of has its own automatic white balance, so in some scenarios it will white balance away the color cast introduced. When the footage goes back to normal white balance, you may see the opposite color cast.

To phrase it differently: You may get an un-intuitive effect where the color cast disappears and then you see the opposite color cast when the footage cuts back to normal WB.

What this depends on:

1- Complete white balance adaptation is most likely to occur when the audience is viewing the results in a dark room. The only reference white is in the image, so your eye/brain will eventually (after about several seconds) white balance to that.

Adaptation is least likely to occur when viewing the results in a situation with lots of reference white- i.e. a computer monitor, with lots of reference white in the interface. Your eye/brain will see the reference white as white.

In between the two situations you have things like watching a consumer TV (some with 9300K color temperature) in a room lit by fluorescents or incandescent lighting (~5000K - 2800K). A high degree of white balance adaptation occurs.

2- The brightest thing in an image helps your eye/brain determine what is white. If the highlights are de-saturated, white balance adaptation will be a lot less. You may get this if you are shooting on film (it tends to desaturate highlights) or (not sure) if shooting on video and the highlights are hitting the knee area.
Changed in white balance in post do not get knee effects and (in my experience) are strongly susceptible to white balance adaptation. Maybe you should use secondary color correction to limit the tint to non-highlights.

Angle in relation to your eye also plays a factor... things in peripheral vision seem to be weighted less. For example, if you have two computer monitors in your field of view (with different white points), your eye/brain will usually slowly white balance itself to the monitor it is looking at.

3- If a color is highly saturated, your eye will not white balance to it.
i.e. street lights, golden hour- the sun reflecting off a car actually appears golden, not white as it otherwise does (at least where I live in Toronto Canada), household incandescents (about 2800K- white balance doesn't go all the way).
If you trick a camera's WB in a strong way, then you will see the effect and your eye won't get rid of it.
*Disclaimer: It's a bad idea to look at the sun. It may also be a little unsafe to stare at the sun reflecting off a car.

A complication to this is that different display devices have different color temperatures. You may have incomplete white balance adaptation when monitoring at D6500 (supposed to be the standard; many LCDs are close to this) while you may have complete adaptation when watching on consumer televisions (much higher color temperatre, which makes them brighter). Or vice versa. The monitoring standard is supposed to be D6500.

The standard for computer CRTs I believe is 9300K.

4- A bit speculative: By default, your brain does not pay attention to changes in color temperature. When you walk from indoors to outdoors, you don't pay attention to your eye's shifting white balance. We tend not to pay attention to small changes in white balance (unless they're extreme).

This may explain why people don't notice that the mis-white balance isn't doing what they intended (if they were aiming for subtle effects).

November 19th, 2005, 09:20 AM	#1
Scott Spears Regular Crew Join Date: Jan 2004 Location: Columbus, OH Posts: 65	New Indie Film Tech Tip: White Balance Hey Folks, I finally got around to making a new Indie Film Tech Tip on White Balance. (I've shot 6 features this year so free time has been tight.) This tip shows you the basics of how to use the White Balance feature on your camera to create different looks for your projects. It's a Windows Media file and runs around 3 min. and 14 sec. Watch and enjoy. http://www.scottspears.net/filmmakpg3.html Scott __________________ Scott Spears Emmy Winner Cinematographer http://www.scottspears.net IMDB listing: http://www.imdb.com/name/nm0817387/

November 19th, 2005, 04:05 PM	#2
Glenn Chan Inner Circle Join Date: Jun 2003 Location: Toronto, Canada Posts: 4,750	As I argue in this thread http://www.dvinfo.net/conf/showthread.php?t=53844, tricking a video camera's white balance may not produce the effect you thought you had. Your eye sort of has its own automatic white balance, so in some scenarios it will white balance away the color cast introduced. When the footage goes back to normal white balance, you may see the opposite color cast. To phrase it differently: You may get an un-intuitive effect where the color cast disappears and then you see the opposite color cast when the footage cuts back to normal WB. What this depends on: 1- Complete white balance adaptation is most likely to occur when the audience is viewing the results in a dark room. The only reference white is in the image, so your eye/brain will eventually (after about several seconds) white balance to that. Adaptation is least likely to occur when viewing the results in a situation with lots of reference white- i.e. a computer monitor, with lots of reference white in the interface. Your eye/brain will see the reference white as white. In between the two situations you have things like watching a consumer TV (some with 9300K color temperature) in a room lit by fluorescents or incandescent lighting (~5000K - 2800K). A high degree of white balance adaptation occurs. 2- The brightest thing in an image helps your eye/brain determine what is white. If the highlights are de-saturated, white balance adaptation will be a lot less. You may get this if you are shooting on film (it tends to desaturate highlights) or (not sure) if shooting on video and the highlights are hitting the knee area. Changed in white balance in post do not get knee effects and (in my experience) are strongly susceptible to white balance adaptation. Maybe you should use secondary color correction to limit the tint to non-highlights. Angle in relation to your eye also plays a factor... things in peripheral vision seem to be weighted less. For example, if you have two computer monitors in your field of view (with different white points), your eye/brain will usually slowly white balance itself to the monitor it is looking at. 3- If a color is highly saturated, your eye will not white balance to it. i.e. street lights, golden hour- the sun reflecting off a car actually appears golden, not white as it otherwise does (at least where I live in Toronto Canada), household incandescents (about 2800K- white balance doesn't go all the way). If you trick a camera's WB in a strong way, then you will see the effect and your eye won't get rid of it. *Disclaimer: It's a bad idea to look at the sun. It may also be a little unsafe to stare at the sun reflecting off a car. A complication to this is that different display devices have different color temperatures. You may have incomplete white balance adaptation when monitoring at D6500 (supposed to be the standard; many LCDs are close to this) while you may have complete adaptation when watching on consumer televisions (much higher color temperatre, which makes them brighter). Or vice versa. The monitoring standard is supposed to be D6500. The standard for computer CRTs I believe is 9300K. 4- A bit speculative: By default, your brain does not pay attention to changes in color temperature. When you walk from indoors to outdoors, you don't pay attention to your eye's shifting white balance. We tend not to pay attention to small changes in white balance (unless they're extreme). This may explain why people don't notice that the mis-white balance isn't doing what they intended (if they were aiming for subtle effects).