Images taken in sunset at 7pm (with back toward the sun) make skin appear orange

Question

Sorry for the stupid question. I take pictures/videos with both (1) iPhone 8 and (2) Sony DSC-WX350.

I notice that when images are taken during sunset at 7pm with my back toward the sun (i.e. facing away from the sun, no glare) my face/skin appears orange. But if taken later at 8pm after the sunset, the face/skin appears normal white.

At 7pm during sunset, there is no average white color, but rather extremes between ultra-pale (in the line of the sun) and ultra-orange (away from the sun). I am using default settings on both cameras.

Is there some spectrum distortion responsible for this?

Here's a very rough small video grab (I apologize for the quality, this was the easiest to post/illustrate the problem). The orange image on the left was taken at 7pm and the normal one at 8pm. All other variables are the same -- same location, subject, and camera (iPhone 8 Video Mode). At 7pm, the sun is behind the subject.

Answer 1

Yes, there is a form of spectrum distortion:

At sunset the light from the sun has to pass through more atmosphere, which scatters the light, but this scattering effect is strong the higher the wavelength of light, therefore the blue end of the spectrum is scattered a lot more than the red, therefore the red end of the spectrum remains stronger at sunset and sunrise, giving direct sunlight a much stronger red/orange tint.

Your camera is either balancing with the sky and shadows that are less affected by this, leaving the orange highlights, or isn't applying any whitebalance correction at all, maybe even detecting the often valued 'golden hour' light and choosing not to compensate.

Image from Reddit

Answer 2

What you are describing is due to a complex assortment of events. First of all, at sunset and sunrise the world appears, bathed in red-orange-yellow light. At these times, sunlight must filter through an extra 20 plus miles of atmosphere. Because the air is laden with water vapor and dust, the blue light component is filtered out. This gives us the golden twilights we appreciate. However warm this golden hour appears, it is muted by the fact that the mechanism by which we see attempts to regulate our view by suppressing much of the ruddiness. We are talking about color adaption. We see with an eye-brain combination, and this mechanism is constantly auto-white-balancing.

Because this phenomenon is eye independent, you can demonstrate the extent of this adaptation for yourself. Cover one eye with a colored filter; red, green, or yellow candy wrappers work nicely. Keep this filter over only one eye and look about. Now quickly remove the filter and blink – first with one eye and then the other. The unfiltered eye saw normally; the filtered eye attempted adaptation, so this eye’s view is despoiled. Don’t worry, both eyes will return to “normal” within minutes.

What I am trying to tell you is, the phenomenon of skin tones and other objects appearing warmer at sunset is natural, but your eyes deceive. The warmth is far greater that you are aware of.

Now film cameras lack any ability to auto-balance out adverse lighting conditions. However, modem digital cameras (incuding cellphone cameras), use chip logic (software) to make these adaptations. While not perfect, modern cameras attempt to neutralize off-color lighting. Some systems are better than others and some systems allow operator intervention.

The warmth of sunset and sunrise often records with more colorization than we naturally see.

Answer 3

Your camera's auto white balance attempts to neutralize any color cast caused by the light source. In the case of the orange images (I'm guessing as I have not seen the images) your camera may be white balancing off of the sky rather than the subject. The bluer light of the sky is making your camera believe that the image needs to be shifted towards orange to neutralize this blue, thus making the subject appear orange, perhaps even more orange than the light appears to your eye. This orange light is often desireable and many photographers shoot during this "golden hour" intentionally.

After sunset both the backdrop (the sky) and the light falling on your subject are blue, so the white balance correctly does what it is designed to do... neutralize the color of the light.