Giving Thought to White Balance and Color Temperature in Digital Images

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Many years ago, back in the days of wired telephones and film, most photographers did not give white balance (WB) or color temperature much thought. Those who did would carry around color-correction filters to screw onto the front of their lenses that would cancel out the color casts of the artificial or natural light illuminating a scene. If you were paying attention back in those ancient times, you may have noticed that some film was marketed specifically for indoor or outdoor use or specific light sources.

My guess is that many digital photographers do not give color temperature or white balance much thought, either. In fact, I pretty much know this because, when I shop on the Web, I see many examples of images that show a definite color cast. This is not usually a big deal unless you are shopping for a ceramic bowl with a cream-colored center and the color cast of the shot makes the bowls with white centers look cream-colored. In photos, generally, we want white things to look white.

Your eyes, by the way, are incredibly good at removing color casts from the scene registered in your brain. White objects look white to our eyes unless heavy filtration is added to the light source or, in the case of a setting or rising sun, the sunlight passes through an abundance of atmosphere, causing the light to shift to a more yellow, or “golden,” cast.

So, if you are shooting a digital SLR or mirrorless camera, or even an advanced point-and-shoot, you may have stumbled across a menu setting or button that allows you to adjust the white balance in the camera. In this discussion, we will talk about how and why you might want to adjust that setting so that, from this point on, I don’t buy a bunch of cereal bowls on the Web that are the wrong color.

Color Temperature

What in the world is white balance, you ask? Well, basically, it is a setting that tells the camera how to register color temperature. Um, what does “temperature” have to do with “color?” Well, color temperature is a measurement of the hue of a particular light source. It is measured in degrees Kelvin. We measure cold and heat with thermometers calibrated to show us degrees, so how come we are talking about color using the same unit of measure? Well, thanks to Lord William Thomson, the 1st Baron Kelvin (a British engineer and mathematical physicist who was directly responsible for forming the first and second laws of thermodynamics) who heated carbon, an “incandescent radiator,” and noticed that as it got hotter, the color of the carbon changed as it heated, we have a color-temperature scale. The hot-or-cold Kelvin temperature scale starts at absolute freezing 0K (-273.15ºC) while the hue-based Kelvin scale relating to color temperature starts with black as the zero point. The visible spectrum of the Kelvin scale ranges from about 1700K to 12000K or more. To the left of the visible portion of the scale is infrared. To the right is ultraviolet.

Have you ever noticed how the stars in the night sky are different colors? Well, this color is directly attributed to the surface temperature of the star where blue and white stars are hotter than yellow and red stars.

Still with me? Like many subjects we have discussed, you can easily dig deeper into the topic, but, for the photographer, what you need to know is that every light source emits light with a unique hue and that hue is measured in degrees Kelvin. Want to solidify the bridge between Kelvin’s temperature and hue? In his later years, the lord served on the board of Kodak Limited, a British company affiliated with Eastman Kodak. Further tying the “temperatures” together, while adding a bit of confusion, we are accustomed to saying that colors that move toward red are “warm” and colors towards blue are “cool,” even though the cooler colors have higher Kelvin temperatures.

Lighting Hues

So, let’s get back to photography. When you are out taking photos, be it outside under the sun and clouds, or inside using lamps or strobes, the light emitted from every light source casts its own hue on the scene. Fluorescent light has a different hue than tungsten, which has a different hue than candlelight, which has a different hue than quartz, which has a different hue than sodium vapor, etc. Many modern LED lights for video and photography feature adjustable hues, or they might be daylight or tungsten balanced out of the box. These hues can either be captured by your camera’s sensor or film, or it can be neutralized with filters or electronics so that the white interior of the cereal bowl, photographed beneath a “warm” incandescent light bulb, still looks white instead of beige.

As I stated earlier, in the days of film, or if you shoot film today, you can get indoor- or outdoor-balanced film, or add filters to your lens to cancel out the color cast. With digital cameras, you can select a white balance setting for your camera to remove the color cast digitally.

Most digital cameras have the following white balance settings: Auto (A), and then, from warm to cool, Tungsten (light-bulb symbol), Fluorescent (symbol resembling a light tube), Daylight (sun symbol), Shade (a house casting a shadow symbol), Cloudy (cloud symbol), Flash (lightning-bolt symbol), or Manual/Preset. The manual/preset option allows you to dial-in a specific Kelvin-degree setting. One thing you need to know is that these preset WB settings do not guarantee that you will neutralize a color cast. Kelvin temperatures for specific lights are estimates and not precisely matched to each and every light source out there. For example, the sun changes color temperature as it moves across the sky, due to the ever-changing thickness and makeup of the atmosphere that filters the light. Also, we are usually being bombarded by multiple light sources when not in a controlled studio environment. Sitting at my desk here, I have fluorescent lights above, the illumination of the computer screens before me, and cloud-filtered sunlight coming in through the office windows.

White Balance in Photos

Now that we are experts on color temperature and white balance settings, we need to figure out a plan for using this in our photography. And, before I get started down this path, let me assure you that there are a great many different opinions on how to proceed here, so, if you have heard something else, or want to share other ideas, please feel free to fill up the comments section below with your suggestions, tips, or thoughts. Also, know that there is no one correct way of using your camera’s white balance settings. I’ll return to this thought at the end, after I run the risk of stirring the proverbial pot.

There are three basic approaches you can take to white balance: 1) you may leave your camera on Auto WB and let the electronic brain inside your camera evaluate the scene and then try to figure out the best white balance to use, 2) you can observe/estimate the color cast and dial a pre-set WB based on the lighting conditions (sunny, cloudy, shade, fluorescent, etc.), or 3) you can set the WB by manually setting the Kelvin temperature to a neutral (white or gray) point in the scene or on a dedicated “gray card.” The manual method requires that you either add a gray card to the scene in a test shot or calibrate to a neutral area of the frame and then take another photo with the white balance adjusted. Many cameras have specific procedures for measuring a manual WB setting. To figure out how to manually set a custom white balance with your camera, grab your manual, or the Internet, and give it a try.

Whichever method you choose, white balance is something that can also be adjusted in post processing by many photo-editing software systems. If you are shooting RAW images, you will have a greater control of white balance adjustments in post processing. With JPEG images, you may still be able to adjust white balance after the image is captured, depending on what kind of software you are using, but the level of adjustment will be less effective than what you can achieve with the RAW images.

If you correctly select your WB manually, or use a WB preset that is spot-on, when you look at your image on your LCD, or on your color-corrected monitor at home, white objects will appear white in the photograph. Other colors will be true as well. Many times, Auto WB will work great for you, but Auto WB is often confused by multiple color temperature light sources. However, if due to a misreading by the Auto WB setting or an erroneous manual WB setting, the image has a color cast, then you can work on neutralizing that color cast in post processing by using the software’s white balance presets, or an eyedropper tool to select a neutral-colored (usually gray) area of the image so that the software sets a specific white balance to neutralize the hue.

One mistake I have made, many times, is that I will forget to change my white balance back to the original setting after I have tweaked it for a series of photos. I’ve been known to do the same with ISO and Image Quality settings. Ugh. If you always leave your camera on Auto WB, you will never have to worry about taking a full day’s worth of photos in the bright sun with your white balance set to eliminate a tungsten color cast. If you already feel overwhelmed by the multitude of options that your digital camera is presenting to you, please do not feel like you have to now throw white balance onto that pile. I am sure many “pros” will say that I am leading you down a path toward destruction, but I generally set my white balance to Auto and neutralize (or not) in post processing.

Go with the Flow

Remember what I said above about there not being one correct way to go about adjusting white balance? Well, I will stand by that. I’ve said it before, and I will say it again: photography is art. Art is subjective. Therefore, if you take an image that has a decidedly blue color cast, either because you told the camera to give it that cast, the camera was set incorrectly, or the camera’s Auto WB missed, and you like that blue color cast because you feel that it works for that image, then there is absolutely no rule of photography that says you need to neutralize your white balance for that image—or any others.

In my own night photography, I often struggle with how to deal with color casts. I generally shoot with Auto WB and then I debate, in post processing, if I should neutralize the color cast from street lamps or other light sources. There are times where I leave the cast in the image, and there are times when I attempt to neutralize it. It all just depends on how I feel about the image and the effect the color cast has on the mood and feel of the frame. Of course, there are times when accurate color rendition is needed in a photograph, be it for commercial or certain artistic demands.

The bottom line on white balance is that it is up to you, the artist, on how and when to adjust your white balance, or to adjust it at all. Hopefully, this article serves to give you a bit of background knowledge and a plan for how you deal with color casts, moving forward in your photography.

The only time you should definitely, absolutely, remove color casts in your photos is when your product shots on the Web are going to cause me to buy the wrong cereal bowls!

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Where does 'photography is an art' misconception originate? It's certainly not - it's only a craft. You are, nearly always, just making a copy of someone else's (often God's) creation. And that's not art. You might make a really, really nice copy, but you didn't create it, You copied it.

Hi mikes,

Thank you for reading and thanks for sharing your opinion on the arts. Art or not, we here at B&H still enjoy the process of photography and the creative aspects of the craft.

Todd....There is a lot to digest here and I need to read it a second and perhaps a third time. I shoot a lot in an ice rink that has multiple sources of light from the ceilings, hallways and stores around it (the rink is open to and surrounded on three sides by the interior of a large mall). In addition to all the light sources there is a large (think 250' x 30') window wall facing north. The result is a battle with WB, particularly with faces and skin tones. At times, well, all the time, no one setting seems to work although shooting during the day is better than after dark but not with consistency. To make matters worse, the problem seems to be compounded in different areas in and around the rink, understandably. It's definitely not a place to go cereal bowl shopping! I don't have this issue anywhere else I shoot. I've never manually set the Kelvin temperature and don't know if my digital cameras will allow this in the menus in addition to not knowing about it until today. I need to check. They must as all four of them were manufactured after 2008. Or do I need my Kodak Brownie back that I got for Christmas in 1958? What does one do in a situation where there are multiple, bright light sources? WB "Auto" doesn't help. I've basically given up. Thank you!

Hey Tom,

Thanks for being a regular reader!

Do not lose sleep! You are not alone in this technological conundrum. I assume you are shooting RAW, so your easiest plan may be to shoot in Auto WB and then do your adjustments in post processing. Or, pick the dominant light source and balance for it and tweak it in post processing.

Not the easiest, but your best solution might be to invest in a $4 gray card and do a manual balance when you arrive at the rink. Let me know what you are shooting and I can help you dive into the menus to see if you can set your WB manually.

Good luck and thanks for reading!

Hi Todd....I really started getting into photography after moving to China 5 years ago for retirement. So it's still somewhat new to me in the sense that now I take it seriously for the first time in my life. I've had cameras since childhood but was never a big enthusiast. Now I always have a camera with me when venturing out. The first thing I learned in my new life is that there is so very much to learn about photography. It takes years and maybe decades of reading and doing.  It's so enjoyable and the camera almost always disarms people and makes friends! 

This is what I'm shooting with: a Sony HX 100 Superzoom; a Sony RX 100 M3; a Sony A7 with kit lens; rarely, my 12 year old Sony F828; Nikon D 90 with 18 - 105mm kit lens, 85mm macro lens, 55 - 300mm lens. I wake up in the middle of the night thinking about getting a Nikon P 900 that you just reviewed! That will be next, I think, on my next trip home to Cape Cod.

I'll dig deeper into the menus as well, always a good way to learn your camera and to reinforce what you already know, or in my case, find out what I've forgotten! 

I am deeply appreciative of Explora, your writing and the generous sharing of your knowledge. Thanks so much.

Hey Tom,

Without digging too deep, my guess is your A7 and D90 are the only cameras that allow you to do a custom WB adjustment. The others probably do not.

There are probably more than a few online tutorials about how to set custom WB on these cameras, but if you run into a road block, let me know.

I assisted at a night photo workshop last night and one of the issues that seems to always come up is how to adjust your WB. There is really no right and wrong here, it just depends on what you want your final image to look like. If you up your game in post-processing software, you will find more options for adjusting it after the shoot. I keep happily shooting RAW images on Auto WB and enjoying the results.

On to your next note...

Hi Tom. I shook Nikon RAW, and use Capture NX to post process (at least the first step).  If I have a shot that has multiple color temps going on, I sometimes use the control points in NX to selectively change the hue or temp of certain areas.  Sometimes it works, and sometimes it's more of a hassle than it's worth.

Thanks Bill! I post process with Apple's standard software app that comes with the Macbook Pro. It really doesn't help much with severe WB issues, although like Capture NX (that I've heard good things about), sometimes it make nice improvement. Something I need to do is to purchase better photo editing software. 

Hey Tom,

Back in the olden days, Photoshop was a sizeable investment. Now, however, things have changed. If you are just doing basic corrections, I wouldn't hesitate to recommend Photoshop Lightroom (image editing and organization) or Photoshop Elements (a stripped down version of Photoshop photo editing software that does a lot more than you think the stripped down version would do). If you want both Lightroom and the full version of Photoshop, you can subscribe to the Adobe Creative Cloud for only $9.99 per month. Skip your coffee shop once a week to fund your photography habit!

Good luck!

Todd..Thanks! I'll look deeper into getting Photoshop or Lightroom. I have to stop procrstinating and get something better for post. And start shooting in RAW again. I stopped about three years ago and I'm not sure why. Time for a change. Look forward to your next article!

Bill, great stuff. Thanks for sharing and helping a fellow photographer!

Thanks Todd, for the explanation. I'm a late entry to the DSLR world, having bought my first DSLR from B&H in December 2013. I got into photography in 1980 when film was the only option. Back then, we had films balanced for daylight and tungsten; tungsten, or incandescent light bulbs, I think are no longer available. Neither are tungsten balanced films, other than CineStill 800.

I approach shooting digital as if I'm shooting film. Generally, I set my white balance to daylight since I'm shooting outdoors when the sun is abive the horizon. Now, I did set my white balance to auto when I was shooting basketball games since I didn't know what lighting was used. I figure that targeting for daylight suits the mood for the day. I haven't tried usiing auto white balance for shooting a sunrise or sunset, but that should be an experiment that I should try.

Hi Ralph,

No such thing as late to digital...only fashionably late!

Approaching digital as you approach film will pay dividends as you get more familiar with digital. Remember, you can always set your WB, and see how a test image looks on the LCD screen. If the tint is obvious, change your settings. Unless, of course, you like the tint!

Of course, you can always shoot RAW and have a pretty good control of the WB in the image after the capture.

Thanks for reading and writing in!