Weird Colors and White Balance

During a workshop this past weekend, several folks commented about having trouble with their images looking yellow or having other weird color casts. This is generally solved by changing your White Balance Settings.

What is White Balance? Back before we had miniature super computers in our cameras, film photographers would use different film or filters to prevent photos from getting weird color casts based on the temperature of the light they were shooting in. Being able to adjust white balance in your camera is one of the great advantages of digital photography.

However, if you think about your camera as a computer, it has to be programmed to mathematically recognize white, which sometimes it does quite well. White balance basically tells the camera “this is white” and it then shifts all colors based on what it believes is white.

So, why is white not always white? Light has a temperature. That temperature causes us to see the light as more blue or more yellow and it can dramatically impact how all colors look.

For example,we once lived in a house where we’d painted every other wall  a nice, neutral gray. One of those walls was in the kitchen, which was open to the great room where two more of the gray walls were located. If we had florescent lighting turned on in the kitchen only, the gray wall in the kitchen looked robin-egg blue while, in golden morning light, the gray walls in the great room turned a soft lavender. The difference was so striking that we once had a guest ask us why we had painted the walls different colors.

The walls were painted the exact same color from the exact same paint can. The difference in color that we see is caused by the difference in the color of the light striking the walls.

This means that in the great room, I needed a different white balance setting from the kitchen to make white look white.

Auto White Balance usually works great in my camera. It has worked great for me most of the time in 5 different models of digital cameras now, even going back to the early 2000’s. As the algorithms in the camera’s computer have improved with each camera upgrade, the percent has probably gone from 75% of the time to 90% for casual shooting.

But then there are the times when it doesn’t work so well.

Auto White balance often fails when:

  • The temperature of the light is outside the range of temperatures your camera’s Auto White Balance is programed to deal with.
  • There are multiple sources of light with different temperatures lighting your subject (e.g., daylight coming through a window plus incandescent bulbs plus florescent bulbs all in the same room. Or, if you’re using flash indoors, most flash units are the temperature of daylight, so that will also create the same kind of mix as in the first example.)
  • Your subject contains a lot of one color or a limited range of colors, which can fool your auto white balance into thinking the light is cooler or warmer than it is, depending on the dominant color(s) in your subject.
  • You are shooting in the golden hour around sunrise or sunset. This is not so much a failure of auto white balance as an over application. Auto white balance will often eliminate the golden cast to the light, removing the warm glow that we usually find quite pleasing.
  • You need the white balance to be absolutely accurate so that colors are represented truly (e.g., a product photo).

So, let’s say you’re shooting away and all your images look really yellow. What to do?

Before we go through the white balance adjustment options, let’s start by saying if you have set your camera to save your images in the RAW format, one option is not to worry about white balance and to set it in post-processing on the computer later. The down side to this is that your white balance accuracy will be dependent on your eye, your memory, and your monitor. If you really need exact colors, this is not the best way to achieve white balance (e.g., product photography, art reproduction, etc). If you just need it to look good, this works very well and can save you some headaches.

That said, even if you are using the RAW format, you may prefer to have good white balance in camera as well. It can make it easier to judge your images when you are not distracted by strange color casts. So here are some options:

First, check to see what White Balance Setting you’re currently on. If you’re on Auto, try picking another pre-programmed setting that best matches your situation. Indoors this gets trickier all the time because we now have all kinds of bulbs that come in all kinds of temperatures. So if your light looks warm to you, try setting the white balance to tungsten (incandescent bulbs). If the light looks cool, try florescent.

Second, you can try setting the temperature of your white balance using the “K” option for Kelvin temperature. Daylight during mid-day is around 5000-5500K. If you change the K value to something higher, your image will look warmer (more yellow). If you change the K value to something lower, your image will look cooler (bluer). You can experiment with this to see if there is a value that works particularly well for your situation, but I find the next method to work better.

Third, if you don’t need the colors to be absolutely correct but you’d like to be able to get your white balance pretty darn close in-camera without having to depend on your eye/monitor later, use a white balance target and take a picture of it in the same lighting conditions you’re going to shoot in. You can purchase a very exact neutral target for this purpose, you can use a white sheet of paper, or you can simply look for something in the same light that is neutral (white works very well for me). The target will be more accurate, but under most circumstances, anything white is good enough. The target must occupy a good portion of the frame for this to work, so zoom in.

Follow your camera’s instructions to set the photo of your target as your custom (Canon) or preset (Nikon) white balance. This will tell your camera “this is white in these lighting conditions” and your camera will measure what white is from that image and then adjust the white balance accordingly. This is a 3 step process:

  1. take a shot of something white/neutral
  2. tell your camera “use this image to determine what’s white,”
  3. set your white balance setting to use the “custom” (Canon) or “PRE” (Nikon) white balance.

This is a really important thing to do if your other white balance settings aren’t working well and you’re saving your images as JPEGs. It’s more difficult and sometimes impossible to fix white balance in JPEG images later.

Fourth, if you are shooting in circumstances where the color must be absolutely correct (i.e., mathematically correct vs to your eye) such as product photography, use a tool like the X-Rite ColorChecker Passport to set your white balance in camera and to also calibrate individual colors during post processing. This is a combination of exactly calibrated targets and software used in post-processing to ensure your white balance and colors are correct. Most people do not need this tool. However, if you do any product photography or art reproduction work, as I do, it is a huge time/headache saver.

But what if you’re white balance is making white too white? This used to be a problem in older camera models. I would get up at the crack of dawn or time my shoot around sunset to get that beautiful golden glow in the light and then my white balance would take it away! My 5D Mark III seems to leave my images nice and warm in Auto White Balance. But, if your camera is off-setting the light more than you want it to, try setting your white balance to florescent. Or, set a Kelvin temperature for the white balance that gives you the nice warm glow you’re looking for.

Finally, a word about flash. When you are using flash indoors, you can help prevent white balance confusion by using gels on your flash to match the temperature of your flash to the indoor light. If we revisit my first example:

Even though I was able to get the skin tones back to natural looking, the rest of the scene still looks a bit warmer than it did in real life. If I had gelled my flash to make the light temperature of the flash match the light temperature in the room, all of the colors could have been white balanced to look right. As it is, because some areas are more lit by the lighting in the building while others are more lit by my flash, it’s harder to achieve good white balance consistently throughout the image. Of course, there are many other problems with this image, so imperfect color temperature is the least of my concerns! 🙂

If your only flash is your pop-up flash built into your camera, here is a do-it-yourself project to create gels for a pop-up flash, but you can also buy gels. Here is a set available for pop-up at Adorama.

For speedlites/speedlights and other strobes, there are lots of options out there for gels.

There are a lot of great resources out there on how to gel your flashes. Since this post is already too long, here’s an article by the Strobist, who has many, many great articles on using speedlites.

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