OK, we’re going to get nerdy here. There are many different kinds of artificial lights, and then there is the light from our sun, commonly referred to daylight. If you want to read up on light color temperature, Wikipedia has a great article.
For artificial lights, they generally fall into a couple of different classes: warm, neutral, and cool.
Warm lights are lights that are tungsten, incandescent, candles, etc. Neutral lights are what you generally see in most retail stores, and nowadays usually consists of fluorescent or LED lighting. Neutral light usually sits between 3800K and 5000K. Cool lights are generally any light that has a color temperature above 5000K.
For photography, if you’re shooting ambient light, it’s going to be all over the place. If you’re shooting with continuous “Hot Lights” then it’s generally on the warmer side (2800-3200K), and if you’re shooting with the newer LEDs, the good ones are tunable, but otherwise they’ll be on the cooler side, and if you’re shooting with a speed light or studio strobe, it most definitely will be on the cooler side, usually at least 5500K, but sometimes upwards of 6500K depending on the quality and power setting.
This all leads to an interesting question: When shooting people, is there a best color temperature to use that renders more pleasing skin tones? Searching Google leads to lots of articles on how to light for skin tones, but very little in the way of whether to use warmer or cooler color temps for your lighting. With that being said, generally, pros tend to err towards warmer color temperatures (i.e. Tungsten) because it tends to look better. This is why much of our indoor lighting for houses is generally pretty warm.
I thought I would put this to the test and take some pictures using a studio strobe at it’s native color temperature, which is advertised to be ~5600K, and then that same strobe, but gelled with a CTO gel to get the color temperature down to roughly what a tungsten hot light would be, which is ~3200K, then compare the two and see what it looks like. Note: the color temperature is going to vary a little depending on the power level of the strobe, but it should be roughly correct.
So lets start with a standard bare strobe with no color correction:
Here’s the color checker chart:
So we can see we’re correctly white balanced for the light in our software, now lets see what yours truly looks like under the exact same light with the exact same white balance in software:
I look like a caucasian guy. If anything, my skin is rendering a bit on the flat or gray side partially because I’m one of those awful people that has a neutral skin undertone. I am however cursed with a pretty bad complexion, so there are parts of my face that are rendering as blotches of color. I guess this is what happens when you’ve been a life long sufferer of super severe eczema.
Let’s look at the same light, but gelled to 3200K:
Again, we can see that we are correctly white balanced in our software. Let’s see what I look like under this same light:
Hmm… that’s interesting.
Let’s look at the two color checker cards side by side. The one on the left is 5600K the one on the right is 3200K:
We can see that even though the the white balance between the two matches, the colors don’t exactly render the same way.
Let’s look at me side by side, again left is 5600K, right is 3200K:
Again, very interesting. Keep in mind some of the color you’re seeing is due to my very unfortunate complexion.
So does the color temperature of your light effect the skin tones in photography? I would say yes. Which one looks better? That’s really a subjective thing more than anything else.
The important thing to take away here is that you should be cognizant of the fact that some people might look better in warmer light and some might look better in cooler light and adjust accordingly.
Till next time.
For this post, let’s talk about taking advantage of white balance to enhance your scene.
I’ll start with a mantra: White Light is a Lie. I’m a long time reader of Strobist, and if there’s one thing I’ve learned over the years it’s that white light has its uses, but largely is a subjective creative choice that can be manipulated in the camera, or manipulated with colored gels if shooting with a speed light or studio strobe.
Let’s take the image above. I was recently photographing an event and saw a group of youngsters outside playing hacky sack. It was evening and the sun had already dipped down under the horizon and they were trying to get the last game or two in for the remaining minutes that the light was still there enough to see by. It had been mostly overcast throughout the day and at this point, the sky had light cloud cover.
I took a quick step outside and grabbed a number of frames, the one above being the best one.
Once I got the images pulled into the computer, I initially did a white balance that looked like this:
You can see that it’s evening time, you can see the warm light from inside the building spilling onto the concrete in the foreground, and spilling onto the skin of the people in the frame.
Looking at the Adobe ACR data, the white balance was 8300 Kelvin. Very blue, very cool ambient light. When I did the initial WB, I pulled the reading off the concrete that didn’t have the warm light spilling on it.
On its own, white balanced like this, this could be a totally serviceable image, however, we can enhance the mood and feeling a little bit by adjusting the WB in ACR to something that is a bit more evocative of outdoors during the late evening.
The first modification, I set the WB to Daylight in ACR:
That’s better, and what it’d probably look like if you were shooting daylight balanced film, but not what I was envisioning. The Daylight WB setting in ACR is 5500K.
I then went to Tungsten WB in ACR:
Whoa. That feels like a bit too much blue. The Tungsten WB setting in ACR is 2850K. We need something between daylight WB and Tungsten WB in ACR. Good thing I shot raw.
For those of you who spend any amount of time shooting with flash indoors, you’ll know that many times, you have to CTO your flash to get it match the lighting indoors if you are blending the two. I primarily use Rosco lighting gels, and their range of CTO gels (1/8 to full CTO) with flash results in the following white balances in Kelvin: 4900K, 4500K, 3800K, 3200K, and 2900K.
When I shoot interiors that are lit warmly, I often end up with my white balance set at ~3800K. This still allows me to render the interior lighting to be anywhere’s from roughly neutral to a bit on the warm side (always a good thing if people are in your shots), and since a 1/2 CTO on a speed light or studio strobe lands at 3800K, gives me 3/4 and full CTO if I want to warm my flash, 1/2 CTO if I want it neutral, and 1/4 and 1/8th CTO if I want to cool if off relative to the camera WB. Many interior lights nowadays are generally 4000K to 2800K depending on the type of light.
Being that I was just inside shooting right before this image was taken, and actually had my camera WB set to 3800K, I decided to make my WB center 3800K. It’s right between 5500K and 2850K and falls nicely where a 1/2 CTO gelled flash would be if I wanted to do that, and if I wanted to, I could push my flash into CTB gel territory and match the color of the ambient light outside. That resulted in the image at the top of this page.
So what’s the takeaway? If your camera or post processing software supports it, don’t be afraid to explore the color temperature or white balance of the light in your image to enhance its mood and feel. You’d be amazed at the effect that it can have.