Exercise: Judging colour temperature 1
Make three images of something that does not have a particularly strong colour, a face maybe, one in full sunlight at the middle of the day, one in shade at the middle of the day and finally one in sunlight when the sun is close to the horizon. Ensure that the camera white balance is set to daylight for all three images.
I believe that photographic colour temperature was determined by heating a block of pure tungsten to a point where its colour became so white that it matched the colour of the midday sun in central New York, its temperature taken, and light temperatures of different settings worked out from that datum. A somewhat unusual method of calculation, but it did provide a datum and colour scale to work with and allowed descriptions to be ascribed so that known filters could be used to ‘correct’ the light for photographing at different times of the day with standard results.
There is clearly a difference in the colours of the faces due to the intensity and colour of whatever light is falling on them. The light in full sun at midday is whiter than that taken when the sun was near the horizon early in the morning and the light in the shade is somewhere between the two.
What I have perceived from this short exercise is that the light in full sun at midday presents flatter, washed-out planes to the face and more contrasting shadows than when the sun is close to the horizon. Here there is more red in the light and provides better skin tone than either of the other two. The shade image allows more fine detail to be observed because the light is very even all through the image but has low contrasts and poor colour rendition and also tends to lack any umph!