How good is the visual system in humans at discriminating colour shades or hues (millions)? What difference does it make if they are processed or compressed images (of natural colours), to the discrimination?

it`s an interesting question, and reminds me of an argument I had some time ago with a fella that wanted to buy a 64 million color GFX card, I explained that the human eye cannot detect the differences between these and thus he was wasting his money, IIRC 16 million colors is about the limit.

Answers summarized here:

 

http://www.stanford.edu/class/ee368b/Handouts/09-HumanPerception.pdf

 

 

or... with further explanation here:

 

http://micro.magnet.fsu.edu/primer/lightandcolor/humanvisionintro.html

Cheers for those links. It's been a while since I looked all that closely at anatomy and so on --the Bio terminology might need a review on my part. Interesting that the 2nd article uses video cameras as an analogy. The first one looks like a good overview or intro to what's happening in this field (btw how old is the 1st one?)

 

What I'm after is any studies (can't find much) about what effect modern image and colour processing could have on discrimination. Maybe I'll need to do the study myself, or something (I asked a lecturer the other day about doing an Optometry course, he said "sure, but it won't count towards the qual.")

 

I read that post (here) by that Honours stud. who asked for some participation in a colour experiment, and wondered about what difference there might be between colours on a screen, and 'natural' colours. Maybe someone already knows...

I can't see how it would matter. "Color" itself is perceived, and thus interpreted by firing patterns of the cone (and, too a minor extent, rod) receptors in the retina. I can't imagine that the source of the frequncy of incoming light plays too big of a role, except perhaps in color saturation/intensity.

 

Let us know what you find.

it`s an interesting question, and reminds me of an argument I had some time ago with a fella that wanted to buy a 64 million color GFX card, I explained that the human eye cannot detect the differences between these and thus he was wasting his money, IIRC 16 million colors is about the limit.

 

That's interest, but I think with enough combining of the 64 million colors you could see a higher detail than just 16 mil. But really pointless, I agree. Your eyes my pick up the difference, but you probably won't.

No... that's just it. If you familiarize yourself with the links above, you will see that there are pretty clear limitations imposed by our perceptual equipment (i.e. eyes).

hmmmmmm, yeah you can only see so closely with a microscope before you need an electrone microscope.