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[Reply #15 on:]

Blue is down the spectum so apear brighter

The human eye (I assume we're talking about human eyes here) is least sensitive to blue light (lower frequency then green).

You see this in the weighting given to blue in the RGB to YUV conversion, which is less than half that given to red.

Peak sensitivity of the eye is in the green section of the spectrum.

[Reply #16 on:]

We have a cooker with a blue LED display and the colour appears to cause excessive flourescence which I feel is possibly a spectral sensitivity peak of the human eye.

What you are seeing is the fact that blue light is bent less during refraction than any other colour. Consequently is is more difficult for the eye to focus blue light. This explains why blue snooker balls appear to have a glow round them.

There used to be a dolly blue factory in Backbarow in the English Lake District.
http://en.wikipedia.org/wiki/Backbarrow
The surroundings were covered in the stuff and this gave everything a soft edge that was most unpleasant to look at. It has since been cleaned up and now you would never know.

Finally a photon of blue light has more energy in it that a photon of any other colour so this gives a greater kick to the retina when on impacts on it.

[Reply #17 on:]

@Groove, ok so i have wierd eyes that are extra sensitive to blue and purple, now that i've had cataracts removed i see the world in a whole new light so to speak including sensitivity to ultraviolet which is normally blocked by the human eye but not by the synthetic lenses they implant

[Reply #18 on:]

@ GrumpyMike,
I remember the dolly blue factory (my granny's shop used to sell it in little muslin twists) and the river below the factory also ran blue!
Difficult to imagine that level of obvious pollution being tolerated these days.

@P18F4550:
I once read that cataract patients were employed as spies to read morse from UV lamps from subs offshore.
(Don't know how true that is, nor can I remember where I read it!)

[Reply #19 on:]

I haven't heard that one, alot of people who have had this done say colours are more vivid, im used to it now but to start with everything looked purple for a while even clear blue sky

[Reply #20 on:]

Who remembers the "blue-whitener" they put in soap powder

[Reply #21 on:]

I think they still do:-
http://en.wikipedia.org/wiki/Optical_brightener

Or at least they did:-
http://en.wikipedia.org/wiki/Bluing_%28fabric%29