If you look at a white snow-covered scene, your brain takes over and manipulates what you see, so that it matches your expectation of what white should look like. So, what you see, even under differing lighting conditions, is white. If you put a camera in the same scene, it does not make any such adjustments and adapt to a certain expectation. The camera will simply record the colours that are present in the scene.
‘White’ light visible to humans can actually vary in colour from reddish orange to greenishblue. This variation is usually described as a temperature range, with warm being the red end and cold at the blue end, and is usually measured in degrees Kelvin using a colour meter. Confusingly, the higher the colour temperature, the cooler…