I am shooting pictures of two different environments with different color temperature of lights and I want to show each environment as it is seen by the naked eye, one being much warmer than the other. Know that I need to turn Auto White Balance off, but what should I set it to in order to demonstrate the different light color in each environment.
We see with our eyes and brain. When we move from place to place under different lighting conditions, our eye/brain combination make adjustments. In other words, we undergo color adaption and dark adaptions, these are involuntary functions. This action is eye independent. Place a colored filter over one eye only and glance about. The filter can be photographic or colored candy wrappers. The key thing, filter only one eye, hold the filter in place for a minute or two. Now remove the filter and look about blinking fist the left than right eye. You will then see the magnitude of this involuntary white balance and sensitivity adjustment.
This eye/brain action far exceeds the speed and magnitude of the camera in this regard. Bottom line, you can show off color images, but they will not likely match what we humans experience.
This eye/brain magic is the secretion rhodopsin, a dye (visible violet) that bathes the light sensitive cells of the eye and changes their sensitivity to match environmental conditions.
Try the above experiment, you will wounder and be amazed.
On sunny day go to shadow and take a photo (of shadowed object). Set first temperature/white balance to daylight/5500k (Kelving degree). Second photo set temperature to shadow/7000K. And you will have two photos, first with wrong white balance, bluish and second with correct one.
Same can be demonstrated with inside photo with tungsten light. First set to daylight, second set to tungsten/3000K. The first will be wrong, orange, the second will be correct.
Here you can find reference about which temperature to set for particular light.
For practical reasons, I would choose a sunny white balance. Our definition of white is the sunlight itself.
Then, take your other photos with the same white balance.
Of course, the resulting photo will be drastically colored. A tungsten illumination will look way too orange than our eyes perceive it because our eyes actually auto-white balance.
One setup you can do is putting two different lights in different rooms or distant lamps you can see at the same time in your house.
When you put a white paper illuminated with each light and you see them at the same time, you can actually notice the difference. That way you can edit your image as you perceive it.
But let me think of a more methodical workflow; you need a tripod.
I. Take a photo with the sunny white balance setting.
II. Take a photo with a custom white balance, using a really neutral gray card.
Not every gray card is neutral. It needs to be of a reliable brand like Xrite. If you do not have one, use an inkjet white paper with the highest "witness" number you can find.
III. Now on Photoshop or Gimp, put one shoot over the other. Let's say you put the sunny as a base and over it the white balanced. Define a transparency level that merges the two in a more natural way that still reflects the color cast of the sunny balanced shot. Let's say you use a 50% opacity.
IV. Use that same method with the other illuminants. Keep the same opacity so your tests are consistent.
Ordinarily, humans experience colors independent of illumination temperature.
Yes, there are edge cases, but ordinarily humans experience the same blues, reds, etc. as the same blues, reds, etc. in warm and cool light.
The edge cases include when we are paying careful attention as when mixing paint colors. Then we control the light source by which we are viewing. But most of the time we are not paying careful attention.
A camera doesn’t accurately represent the human eye…the human eye is mostly monochrome rods, foveal vision is about five degrees in the center of the eye and each eye has a blind spot dead center where the optical nerve connects.
What we see is an interpretation of visual stimuli processed by our brains. It easily misses gorillas among when we are counting basketballs.
You can make pictures and say they represent human vision. But no matter how rigorous your approach, it will be make believe…ok, it will only be a model and all models are wrong though some are occasionally useful.
With rigor and thoughtful consideration of the vast differences between photography’s limits and human visual experience, yours might be.