I don't think it's really either. It's not a fact because different people and Животные see different things based on the cones in their eyes; it's not an opinion because I don't see it as a "belief" или something Ты can choose.
Also hey, Болталка fact from the UChicago essays: The mantis креветка, креветки can perceive both polarized light and multispectral images; they have the most complex eyes in the animal kingdom. Human eyes have color receptors for three Цвета (red, green, and blue); the mantis креветка, креветки has receptors for sixteen types of color, enabling them to see a spectrum far beyond the capacity of the human brain.
oooo very interesting question, actually, according to what i know, like, from school, books, docs and different information i unconsciously collected over the years, color comes from us, not objects and have something to do with light, lol. so some Животные can see color that we can't see and we can see Цвета that some Животные can't see...however, the object appears to us a certain color, not because of our conscious decision, but because our brain receives the light reflected of that object in a certain way and we perceive it to be a certain color, therefore, no matter how much we want something to be blue или purple или red, it's always going to be that color which our brains are wired for us to see. So, i guess even though color is an illusion and appears differently to Животные and even some people, because we have to choice in the matter of which color we see, it must be a fact...i think, lol! :D
(Your Вопрос is confusing me) Well, I suppose it means how Ты define 'colour'. (I'm still confused. Please explain to be what Ты meant otherwise I'm going to spend the rest of the день thinking about this ;n;)
It depends entirely on what Ты mean by "color". If Ты are referring to the intrinsic value of whatever Ты are observing, или the value of light reflecting from an object, then that is a fact. If Ты are referring to the assessment of that value, then that is an opinion.
For instance, so long as all conditions are the same, the value of light reflecting from a surface is the same, no matter who is observing it. However, we may all interpret that value differently.