White Balance —Learning to See

Mark Wieczorek
Ice Cream Geometry
Published in
17 min readMay 26, 2019

White Balance 101 — The Basics

Light has a color, known as a color temperature. That is — it can be more warm (orange) or more cool (blue). When you buy lightbulbs they’ll say things like “daylight” or “warm glow” — these are descriptions of the color temperature that they produce.

That “daylight” bulb may have a color temperature of around 5,400 Kelvin. The “warm glow” may have a color temperature of around 2,700 Kelvin. This means that the dominant light put out by that source is around that color temperature.

Source: Wikipedia

This may be a bizarre concept to wrap your head around because you’ve spent your whole life looking at colors under different lighting conditions — and red is always red is always red.

Your brain interprets light on a relative scale. If you’re next to a camp fire and the light is fairly warm (orange in tone), the white plate will still look like a white plate, even if it’s objectively orange.

It takes some time learning to “see” color temperature because you’ve spent your entire life ignoring it. You first have to un-learn something you’ve been doing automatically your entire life.

So how do you learn to “see” color temperature? Easy — You spend time looking at color temperature.

Learning to see Color Temperature

When I shot film, I remember buying film that was “balanced” for “daylight” or “indoors” — but I hardly knew what it meant. I always bought the “daylight” balanced film. People looked a bit orange indoors, but that was fine — it’s just what people looked like indoors.

It wasn’t until I got my first digital camera where you could change the white balance, and even manually set it, that I really started to pay attention & understand what white balance was all about.

I became a little obsessed with it — carrying a grey card around at all times and constantly resetting my white balance as lighting conditions changed. I set white balance in my camera all the time and it’s hard to explain but photos that I took when I did this felt “right” and other photos felt a bit off… Less than right.

One day I was getting ready to take photos for an event — it was in a Manhattan townhouse largely lit with halogen lights. A space for artists to display their work.

As was usual, I took out my grey card and one of the event organizers asked me about it. “Oh well light has a thing called color temperature” I explained — parroting back what I’d read online.

“Oh, what is that like?” Knowing how I could find it but not sure I could explain it in a few words I looked around and saw it. It was still daylight out. Blue light streamed to the windows from the sky, but the warm halogen lights made the walls look orange.

“There, you see? The window sills are blue because they get their light from the blue sky, but the wall right next to it is orange because it’s light by the warm indoor bulbs.”

Source: https://unsplash.com/photos/iRyGmA_no2Q — You’ve seen both colors of “sand” your whole life, but only ever noticed the difference at sunset.

The second place was at the beach at sunset. You don’t live near a beach? Don’t worry, really just about anywhere near sunset works. The key is to look at something where you can see both the side lit by the sun, and the shadow side at once.

As the sun sets, this giant orange ball of flame gets closer to the horizon. The shadows get longer, and so do your opportunities to see the difference in color balance.

Take a look at the photo to the left (above on mobile). The areas of sand that are hit by the sun are orange. The areas of sand that are not are blue — from the sky.

If you really want to see this clearly, get something white — a piece of paper, a tissue you found in your pocket, a shopping bag from the store — anything. The roll it up, crumple it up, or make a little tent so that you can see more than one side at once. Wait until the sun is low in the sky and look at it.

You’ll see what I saw — both color temperatures simultaneously.

If you’re lucky, the sun will pass behind a cloud for a brief moment and everything will snap into a single color temperature — and once the cloud passes, you’re back to two different color temperatures. For that brief moment, your brain reset its frame of reference to “sky color is neutral” and you lost the ability to see color temperature.

Now, years later I can see color temperature anywhere at any time. The light is warm or cool or whatever. In a dark movie theater can I tell what the color temperature of the white/neutral light projecting through to the screen is? No. But when I see two different color temperatures, I notice them immediately.

Fluorescent — Green and Magenta

Source: Wikipedia

Do you remember that 1999 smash hit movie The Matrix? Did you know they used color temperature in that movie to tell you subtle things about reality? The Matrix was the sickly green of fluorescent lights. The “real world” was a more golden orange, like an incandescent bulb. If memory serves in the sequels, Zion was more blue.

So far we’ve discussed Orange to Blue — but color temperature has another dimension — the green/magenta axis.

The influence of the green/magenta axis isn’t as strong. In fact while the warm-to-cool axis is measured in thousands of Kelvin, the green/magenta axis is measured (in Adobe) from -150 to +150. yes, one green/magenta axis value is assumed to be default and the most you can adjust it is from -150 to +150, and usually -10 to +10 is enough. The Warm/Cool axis, however, you can adjust from 2,000 to 50,000.

A sodium-vapor lamp (source: Wikipedia)

One note about color temperature before I move on — light is a spectrum of frequencies. The color temperature is just the predominant frequency — what will make white look “white” to your eyes. Most light sources produce a broad spectrum of frequencies, but tend to be stronger in some frequencies than others. Modern LED lights tend to be stronger in the blue spectrum — more daylight cool. To produce warm LEDs manufacturers simply put a warming filter over the light — to cut down on blue frequency light, emphasizing the warm frequencies more.

There are some examples of lights that just produce a very narrow spectrum of color. Sodium Vapor bulbs (street lamps) work by exciting a gas molecule and it produces a very narrow spectrum of light. This is why it’s so hard to see — for example — blue cars under Sodium Vapor lights. They produce so little blue content that the blue car just looks black.

Modern street lights are LEDs which have their own problems — the blue-ish light confuses wildlife who associate blue light for daylight, screwing up their sleep cycles. This is also why it’s advised to not look at screens (or use an orange “night” app to reduce the amount of blue light coming out of your screen) near bed time.

I’ve learned to see in Color Temperature — Now What?

@lizziapple — one of my closest friends & once upon a time we used to take photos.

Ability to work with color temperature has actually been a core theme of my photographic work for a long time. I’m one of those snobby photographers who always shoots in manual mode & who always sets white balance in camera. My goal is to get the shot in the camera through my mastery of light and the photographic process — and then use post-processing for just a few touchups and to fine tune the image I’d already captured.

The photo to the left (above on mobile) is one I captured in camera .

The blown out sky & the warm tones were very much what I was going for, and was a hallmark of my photographic style for many years. I chose this style, partly because I loved the way it looked, and partly because it requires a mastery of exposure & white balance to get this look.

It also required really knowing my equipment — in what way and why that equipment would “fail” — that is when the lens would flare, and when the sensor would “blow out” (go to pure white). I used one camera + lens for all of my photographic work for years.

White Balance 202 — Daylight White Balance

There is such a thing as “daylight” white balance and you can select it in most cameras (it’s the little image of the sun usually). This is about 5500 Kelvin.

Daylight white balance is the color of the light at midday. Why midday? Because there are no shadows at midday. (This is hyperbole, bear with me.)

Noonday Light

During midday, there are two light sources — the sun and the sky, but you can’t separate them.

Camera manufacturers will take the average color temperature of the light at this time and call it “Daylight” — usually a the little sun ☼ symbol. This is around 5500 Kelvin — daylight white balance.

As the sun gets closer to the horizon, the sun and sky split more and more into the Big Ball of Orange Specular Highlight and the Big Blue Box of Softbox Fill in the Sky.

As the sun sets, the color moves more and more towards the warm end of the spectrum — around 3800 Kelvin.

Similarly, the blue sky — freed from being so close to the sun moves more towards the cooler end up the spectrum — around 7200 Kelvin.

While the two numbers may still average out to around 5500 Kelvin of “Daylight White Balance” the two sources of light get further and further apart — both figuratively and literally.

Keeping in mind that your eye sees relative color and not absolute color, which of the 3 options do you choose for white balance?

The warm ~3800 color temperatures from the sun? The cool ~7200 color temperatures from the sky? Or the average — around “Daylight” at 5500?

Why is the Sky Blue? (side note)

Air scatters light. It does a better job at scattering the shorter blue wavelengths than the longer red ones. This causes the sky to appear blue.

As the sun sets, the eastern sky is primarily the blueish light that is reflected back at us from the air. The western sky is primarily reddish light — the longer wavelengths that aren’t scattered as easily — essentially the light of the sun with the blue filtered out. The sunset sky appears reddish because the blueish light has been scattered out and is now lighting up the shadow side of distant mountains or buildings.

http://www.atmo.arizona.edu/students/courselinks/spring08/atmo336s1/courses/fall13/atmo170a1s3/1S1P_stuff/scattering_of_light/scattering_of_light.html

White Balance 303 — Playing with White Balance

So how do I play with white balance in my photography?

The trick is remembering what I said before — on a sunny day there are actually two different light sources. The bright ball of orange in the sky and blue sky.

“Daylight” white balance is around 5500 Kelvin, but that doesn’t mean the sun or the sky is actually giving you that precise color temperature, it’s a sort of blended average of the light from both light sources.

If you set your camera to the daylight color temperature, you’ll be able to see the blues from the sky AND the oranges from the sun.

If you set your camera to the warm sunlight color temperature, it will neutralize the effects of golden hour (and your reason for taking the photos during golden hour in the first place).

There is a third option though — set your white balance to the color temperature of the sky. Your camera has a setting for this — shadow white balance. Often a little house symbol with shaded lines to one side.

Take this photo taken during golden hour. In order to set the white balance, I took an image of a grey card that was completely in shadow (reflecting the sky & blocked from sunlight).

@justbra0

Here’s the grey card — to prove that this was a white balance set in camera. The color temperature of these images was a cool 7150 Kelvin. This was the color temperature of the blue sky in the shadows.

The color temperature of the sun at the time was warm — around 3500 Kelvin.

The following three photos demonstrate what I’m talking about.

The one on the left was taken with the white balance set to a grey card in the shadow — 7150 Kelvin. The middle photo is set to Daylight white balance — 5500 Kelvin. The one on the right was set to 3850 Kelvin — the approximate color temperature of the sun at that time . (Guesstimated — I didn’t capture a grey card image in the direct sunlight. I just went as far warmer from 5500 as 7150 was cool, I think the sun was actually even warmer than 3850.)

Notice in particular the blue rim of light on Justine’s shoulder at the left of the frame. In the leftmost picture (set to sky white balance) it’s neutral. In the center photo it’s cooler. In the final picture it’s obviously sky blue.

Now go back to that photo of Lizzi above (in the fringe top) — I also set the white balance to a grey card in the shade. Her coloring there is very natural — very neutral, and the landscape behind her is warm sunset tones.

There are those who argue that you should always shoot at Daylight white balance — 5500 or so. I partially agree with this, but mostly disagree with this. 5500 will give you a pleasing “accurate enough” white balance throughout the day, but it doesn’t take enough advantage of the fact that there are two different and distinct white balances on a sunny day — direct sunlight (warm) and shadow (blue sky, cool).

Here is the image from above to further demonstrate what I’m talking about.

  • The sun during golden hour is in the warm 4000 Kelvin range.
  • “Daylight White Balance” on your camera will be in the 5500 Kelvin range.
  • The sky during golden hour is in the cool 7000 Kelvin range.

You can set your camera to either “Daylight White Balance” — which will show the shadows as cool (as in the footsteps photo above) or to the cool sky (as in the photos I posted) which will show the shadows as neutral, and push the sun light further into the warm spectrum.

Remember, your eyes see color on a relative scale. Your eyes don’t see things in “daylight” white balance. I would argue that setting your camera to the cool shadow white balance is closer to the way the eyes see light around sunset.

I would rather have neutral shadows and a warmer sun than cool shadows and a moderately warm sun.

This technique has its limits — as the sun really dips low to the horizon, the cool blue of the shadows may not be enough to push the orange into the range that the eye sees, or maybe there’s a blue hazy mist in the mornings, or maybe the sky is an amazing purple. Sometimes you really will just have to guess at the colors in post production to try to recreate them from the hazy memory of what you saw.

I take a grey card photo frequently & re-set the camera white balance often throughout the day. This serves several purposes.

  1. I have references for where the shadows were at several times throughout the day that I can go back to. Theoretically I could just take the grey card shots and set them all to 5500 Kelvin and get a map of how the light changed throughout that day. The time of day, the season, the amount of pollution — they will all change the color temperature.
  2. It’s an easy visual marker for me to see where I changed location or subject or whatever.
  3. I’m constantly recalibrating the images to the current color temperature, so I don’t have to adjust them in post — I get the colors I want Straight out of Camera (SOOC).
  4. I’m constantly recalibrating the camera to the current color temperature — two different cameras will respond differently to the same scene, even if that scene is a grey card.

White Balance Tools — A Brief Review

Note — affiliate links used.

Lastolite 12" Grey Card

Small enough to into your camera bag when collapsed. Big enough to fill your frame. Small enough to block with your body so you can isolate the sky color temperature from the sun color temperature.

I also use it to set exposure using the Zone System (a possible topic for a future blog post). This makes it my favorite white balance tool — I can set both white balance/color temperature and exposure at the same time using the in-camera light meter..

The opposite is white so you can use it as a mini reflector or fan (to blow hair) though I mostly just use it to protect my camera gear from grass and dirt when I place things on the ground. It’s not 100% accurate, but it’s good enough for rock & roll.

ExpoDisc

This tool is specifically designed to “capture the light hitting the object” — you stand at the location of what you want to photograph & the turn it around and use it to cover the lens (it diffuses the light) and take set the white balance to it.

They’re well built, but I prefer the Lastolite grey card. I believe the ExpoDisc is more accurate, but it cannot be used to set exposure — I find that it’s typically +1 stop brighter than middle grey.

I do use this for when I need to set perfect in-camera white balance to studio strobes, but then I have to set exposure to a separate grey card making it a two step process.

Spyder Cube

This tool is designed to work exactly in the way I describe. It’s a cube with multiple faces so you can capture two different color temperatures at the same time. It’s not large enough to set in-camera white balance, but can be used in post.

It also has a metallic ball to tell you where the specular highlight is. It has a deep velvet hole to show you were the darkest color is. It also has white and black surfaces used to show you where the diffuse highlight is.

I like this tool, but never used it in practice. I still prefer to set my exposure to the Lastolite grey card and and I just don’t need that much information in post about where the specular highlight, diffuse highlight and shadow point are and whenever I use it, the results look less natural — too stretched.

Color Checker Passport

If you’re into calibrating your gear, this is a must have. You can use either X-Rite’s software or Adobe’s DNG Profile Editor to create a profile for your camera that (theoretically) allows you to eliminate (reduce) differences in how different cameras produce color.

In practice — I don’t use it much, I just buy cameras whose color profile I like, but in the past I used it a lot & it’s important for where color accuracy is important (product photography) & can help you learn about colors. It has a separate grey card panel as well so it can be used as an all-in-one solution.

It also has neat “warming” and “cooling” patches that are designed to allow you to one-click get a warmer or cooler image.

WhiBal

One of the best tools for white balance. It’s solid plastic — so the same grey through-and-through even if it gets scratched. Wallet size (it’s about the thickness of 2 credit cards). Perfect to take a reference white balance shot if you don’t need to get it in camera (it’s a bit too small, depending on your camera — some cameras will capture color temperature from the center portion of the image, others need you to fill the frame).

It’s a bit shocking how different the color temperature of this tool is next to my beloved Lastolite 12", but I’ve always been happy with the results from the Lastolite. I would say this is more accurate, so if you care about accuracy, just get a photo of this so you can set color temperature in post.

It’s available in larger sizes, but since it’s a stiff plastic, the larger sizes aren’t as portable, but would fill the camera frame. Also as neutral as it is, I find has more specularity (it’s more reflective) than the Lastolite.

Tips for using a Grey Card

12" grey card in action — I think this was a cheap knockoff of the Lastolite I used for a while.

Put the grey card at the subject’s location pointed back towards the light source (as if it’s reflecting the light from the light source into the camera — which is precisely what you want it do). Take a photo of the grey card.

Depending on your camera, you can either set the white balance to the photo you just took (Canon) or you have to capture it first in camera (Nikon) and then I take a reference shot. The reference shot serves as much as to signal to you in post production that this is a new lighting source as it does to give you the ability to “eyedropper” take a new white balance in post to apply to a new image.

Some cameras (Sony) have a weird quirk that no matter what the in-camera settings, it will take the white balance image with a full ambient exposure — meaning that if you’re set up for studio strobes (1/250 sec), it will take a longer exposure, assuming you’re purposefully under-exposing & it’s exposing for middle grey according to the ambient light. These camera companies assume I, the photographer, don’t know what I’m doing and are to be avoided.

To set your exposure, in ambient light it’s easy — just make sure you’re not blocking the light and turn the dials until the exposure meter is in the middle when pointed at the grey card.

For strobes — take a picture of the grey card and look at the resulting histogram. Adjust until it’s in the middle.

When using the grey card with strobes, I usually angle the grey card at a 45 degree angle between me and the strobes — it helps reduce an effects from possible specular reflections on the grey card, plus helps ensure I’m not shadowing the strobes.

The Results

@lizziapple — set to a white balance in the shadows.

Let’s revisit that photo of Lizzi.

I set the white balance in-camera to capture the sky (the grey card was in the shadows).

Notice how the light on her skin is neutral, and the light streaming through the leaves and her hair is warm?

If I had set the white balance to “daylight” the the light on her skin would have appeared blue & the light streaming through her hair would have been less warm.

In many ways, photography is about understanding how a camera perceives the world differently from the way the eye does & playing with that.

White balance is just one way the camera differers from the eye in how we perceive the world. It’s one thing we can play with to alter perception. I would argue that when it comes with this picture — it is a fairly accurate representation of the scene, at least in terms of color temperature.

About the Author

@sodiumstudio — model shoots & portraits mostly

@sodium.nyc — vintage lenses, event & street mostly

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