Yesterday’s Topic: Camera Modes
White Balance is your camera’s attempt to make white be white. That’s really all it is. The camera knows if it can make white show as white, all the other colors will be accurate. White isn’t always white because not all light is created equal. For instance, a tungsten incandescent light bulb (the standard light bulb for the last 100 years, more or less) puts our light that is slightly more yellow/orange than the sun at noon. The measurement of this light is as a function of its temperature on a Kelvin scale, noted with a K.
Direct noon-day sunlight is the standard bearer of this scale for reference sake. It is pretty much at 5000K. Anything higher than this color temperature takes on a blue color and anything lower takes on an orange/yellow color. Back in the days of film you used to have to buy a roll based on the light you anticipated using. Most film was daylight balanced, around 5000-5500. Do you remember using that film indoors with tungsten light bulbs? Things took on a yellow color cast. And florescent lights? Greenish ick. This is also why flashes are set at 5500K, so as to be close to daylight, which is very handy when used as a Fill Flash (a post coming this month).
Digital cameras have the advantage of being able to adjust on the fly for the light coming in. But it can be a tricky business trying to guess the light source properly. Therefore, most cameras have the ability to manually change the white balance if desired. Here is a graphic representation of the various settings yoy might find and their relative value and place on the Kelvin scale.
Why is this important? When using a JPEG setting for file type, the white balance as the camera sees it is set when the file is compressed. No going back. If the camera picked the wrong white balance, the image may be too blue or orange or green. And that sucks. One way around this is to shoot in RAW mode because the white balance is not set, but instead written to a file that accompanies the RAW file. When viewed on a computer the information is re-read and applied, but if the white balance doesn’t match, you can simple tell the computer (either by a slider or by typing in the Kelvin temperature) what the white balance should be.
Try it yourself. Grab a white piece of paper and set your camera to daylight (5000K). Get the white piece of paper under an incandescent or fluorescent bulb and snap a shot. Even on the back panel LCD you will notice the color looks off. Off as in white is not white. Take the piece of paper out into the daylight (if you have it) and perform the same test. Bingo, white is now white. The color white is balanced.
If you don’t want to worry about White Balance, shoot in RAW and set the camera to Auto for the actual White Balance. Otherwise, if shooting in JPEG, be careful around harsh situations when the camera might get tripped up, such as:
- Moving from sun-filled to shade, especially with snow
- Going from indoors to out of doors
- Multiple light sources. In this case, you have to pick one and accept the others source(s) will show as exaggerated
- Large surface areas that are barely offwhite to start with
- High school basketball games
- Underwater (but this is a slightly different reason and why a number of point and shoots have a separate setting)
And check to make sure your camera is metering right. One other thing, you can set a custom white balance if you know the light will be a certain temperature for a certain period of time. This usually involves pointing the camera at something white and using a custom function, so you’ll need to look up how to set it in your manual. I know, homework. But it will help if you must shoot in JPEG and have some tricky light.
If you are looking for more in-depth info or a chance to get totally lost, check out Color Temperature on Wikipedia. It was also suggested to me there is a great explanation in the book Understanding Exposure so you might want to check that out as well.
Next Up: How To Take A Shot
31 Days To Better Photography is a series written by professional photographer Peter West Carey on The Carey Adventures.Com. The series is designed to unravel the mysteries of photography so you can take better pictures. Subscribe here to receive all the updates and bonus material. Your comments are always welcome.
PS, Bunny Yeti Bunny Bunny Yeti
Worlds colliding now…one aspect of my day job is Lighting Design. Granted, it doesn’t directly relate to photography, but there are a few takeaways there. Knowing your light source is a big thing, especially in (relatively) low light scenarios. The color of the light is certainly one thing to be concerned with – and Peter’s scale above certainly drives that point home. But some light sources might illuminate at a given color range, but may not render color on surfaces appropriately. In the lighting industry, a somewhat more important number is the Color Rendering Index (CRI) where the higher the number, the better. Put simply…it’s a measure of the range of colors in the visible spectrum that are present in the light source. If a given color is not present in the beam of light, it won’t bounce off of the surface of that color. So if green isn’t available in the light source, it won’t be apparent to the camera regardless of how well you white balance the shot.
For example: Candle Light and Incandescent are both very warm light sources. One would think that it would not render the cooler colors well, but that’s actually not the case. Despite their place on the Kelvin scale, they both have an exceptional CRI (100). This of course means that once you white balance your photo, you can trust that all the colors will be accurate. On the other hand, a High Pressure Sodium lamp (many yellow-tinted street lights) have a color temperature of about 2100-2500 K, but it’s CRI is quite horrible (only about 24). Greens, Blues and Purples render quite horribly under such a light source, and there’s nothing you can do about it no matter how well you white balance the shot. The solution, of course, is to use a fill light like your flash.
This of course won’t necessarily apply to most situations, but it’s something to be aware of. Especially if you’re a night shooter. It may even be something to take advantage of.
Hope I didn’t get too technical there.
Good additional info, Travis. Thanks for adding it!
still have a problem with white balance.and i still dont know how to use the custom white balance.hmm…
is there no when to use tungsten?flourescent?when im using my camera at night the skin tones usually come out orangey or too yellow.
super beginner…so bear with me.
thanks mr peter.
jac,
When you take the night shots, is there a lot of artificial lights around or is it just the flash on the camera?
To use most custom white balances you would take a photo of a white piece of paper in the light you are shooting in and then go through the menu’s to select “Custom White Balance”. It will then ask you which picture contains your white balance and you select the image you just shot.
Others will, once you have selected the “Custom White Balance”, have a spot in the middle of the viewfinder. Point that to something white and either hit Select or the shutter release to select that spot.
Hope that helps.
thanks mr peter.will do.
have a canon 450d.
will wait for the rest of the series.
very cute daughter…
and your travel photos are breathtaking.