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Muddle mirror silver not a colour

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Zziggy
1162823.  Sun Dec 13, 2015 5:51 am Reply with quote

'yorz wrote:
You wouldn't even use the same colour red for the whole dress, as that would indeed turn out flat. To reflect the folds, creases, texture, etc you need other colours. Simple.

No I know, I was confused as to why you were saying that was why gold isn't a colour (was that what you were saying?) because the same thing is surely true of any colours.

 
'yorz
1162824.  Sun Dec 13, 2015 5:58 am Reply with quote

Wiki gives the most comprehensive answer. ;-p

 
suze
1162862.  Sun Dec 13, 2015 10:07 am Reply with quote

Is the point here that silver is (or can be, at any rate) an achromatic colour? Or in less technical terms, it is a shade of grey.

There are half a dozen mathematical models used to define every colour there is in terms of a small number of parameters. Psychologists studying human vision most often use the CIE 1931 model (also known as the XYZ model). Television and computing use the RGB model (or the HSV model, which is a transposition of the RGB model), while printing uses the CMYK model.

The RGB model is probably the best known of these to the layperson, and defines every colour in terms of three parameters Red, Green, and Blue, which can take values between 0 and 255 (0 and FF if we work in hexadecimal, but let's not just now).

The colour (0,0,0) is defined as black, and the colour (255,255,255) is defined as white. (255,0,0) is red, (0,255,0) is green, and so on. Any colour in which the three parameters all have the same value is a shade of grey, and so for instance (220,220,220) is known as Gainsboro, and (152,152,152) is known as Spanish gray.

The colour which is called silver in HTML is (192,192,192) and so it is a shade of grey. But Crayola has been making "silver" wax crayons since 1903, and their silver is in fact (201,192,187), which makes it technically a shade of red. That colour does not have a name in HTML, but it's sometimes referred to as "pale silver" or "Crayola silver".

 
Posital
1162899.  Sun Dec 13, 2015 11:28 am Reply with quote

Well - colour in an object is a lot more complex than just CYMK (or any of the above listed by Suze). Different colours, although they may look the same under one lighting condition - are each seen differently under different lighting conditions. More than the simple RGB/CMYK model would make you expect.

This is the result of colour being a mixture of a continuous spectrum - akin to sound or music. Primary colours could be seen as a way of representing the rich variety of the music world using Status Quo's three chords only.

So although we may only perceive three primary colours, the way the frequencies interact make all manner of effects possible which primary colour theory cannot explain alone.

 
Leith
1162906.  Sun Dec 13, 2015 12:08 pm Reply with quote

I don't know what the elves had in mind, but I suppose silver has two defining characteristics in that that it's a) chromatically neutral, and b) metallic. So it's far more distinctive in its texture and reflectivity than in its hue.

That particular quality of shininess seems to be quite well embedded in our vocabulary for talking about colours, in a way that the visual texture of say, stone or cotton isn't. The B series told us that Greeks of Homer's time called the sky 'bronze', theorized to reflect an emphasis on texture and lustre over hue in the colour language of the time. Our terms for metallic colours seem uniformly less abstract than their purely chromatic counterparts. Are there cultures with words for 'shiny colours', e.g. for the sun and stars, that don't reference precious metals?

 
pmailkeey
1162908.  Sun Dec 13, 2015 12:20 pm Reply with quote

One problem 'we' have with silver is that for the most part, we're 'seeing' polished silver - so is obviously somewhat shiny. Is that shininess hiding its true colour ?

A friend of mine drilled a hole in silver. I looked into the hole and saw pale green. It needs someone to do this again in a protective atmosphere to ensure the surface remains clean silver - and see what colour is there.

Incidentally, it seems 'web silver' is hueless (can be any hue you want), has zero saturation (so hue doesn't matter) and only 75% 'value'. So effectively, silver is 75% towards white from black.

 
PDR
1162918.  Sun Dec 13, 2015 1:21 pm Reply with quote

If you you take a pieces of silver and spray it with matt lacquer the result looks either light grey or off-white (depending on the particular alloy), so I suggest that those are the "actual colours" of silver if you take the reflections away. You can get a similar result if you take polished silver and remove the shine with wirewool or 600 grit abrasive paper, but that tends to get you thrown out of the silversmith's shop and arrested.

Do the same with chrome and the base colour comes out as bluey grey. Nickel looks yellowy-grey, and stainless steel just looks light grey, while most other irons and steels just look medium grey (or rusty).

You can't really compare the paint (and crayola) colours with RGB and HSB models, because the RGB/HSB models describe emissive colour which (no matter what the fancy screen designers tell you) will never ever be able to directly map onto the reflective colour of real objects. Which is rather the point, I think.

If you're interested in *perceived* colour you need also to recognise that the lower-end of the human eye frequency response varies quite a lot, with some people able to detect colours which for others are at the top end of the infra-red range, which is probably why humans can't agree which colour tone match and which clash badly. I've hear it suggested that for a proportion of the population the colour they "see" is significantly affected by the temperature of the object as theses "list below typical visual range" frequencies start to drag the mean colour mixture down a bit.

And the dress was obviously white, before you ask.

PDR

 
Zziggy
1162950.  Sun Dec 13, 2015 3:42 pm Reply with quote

PDR wrote:
And the dress was obviously white, before you ask.

Get out.

 
RLDavies
1163124.  Mon Dec 14, 2015 12:18 pm Reply with quote

Fry's argument that "silver isn't a colour because you can't display it on a computer monitor" didn't impress me at all. It reminded me of the people who say "pink isn't a colour because it isn't in the spectrum". Neither is brown, but I don't think anyone has ever extended that argument to brown.

Colour is incredibly complex, and includes subtleties of perception and psychology, as PDR states. The basic human understanding of what colour is comes from our millions of years of experience with objects in the world, and therefore from reflective colours. Reflective colour is "real" colour, and emissive colour (coloured light, as from a monitor) is only an imperfect copy of that.

 
PDR
1163126.  Mon Dec 14, 2015 12:23 pm Reply with quote

Zziggy wrote:
PDR wrote:
And the dress was obviously white, before you ask.

Get out.


Sha'n't - so there!

PDR

 
14-11-2014
1164064.  Sat Dec 19, 2015 9:02 pm Reply with quote

pmailkeey wrote:
So they said silver is not a colour.

Silver, gold and even pink are defined, supported RGB colour names.

 
crissdee
1164099.  Sun Dec 20, 2015 7:19 am Reply with quote

14-11-2014 wrote:
Silver,


They can call it what they like, this is grey on my screen.


14-11-2014 wrote:
gold


This is a (rather nice) orangey-yellow.

 
Posital
1164377.  Mon Dec 21, 2015 4:04 pm Reply with quote

If I scrape that gold colour off my screen, would I get much for it? Maybe there's a proverb about it?

 
14-11-2014
1168497.  Sun Jan 10, 2016 12:15 am Reply with quote

In Germany the colour gold is more than a defined name of some RGB colour index value.
bundestag.de wrote:
According to Article 22 of the German Basic Law, the colours of the flag of the Federal Republic of Germany are black, red and gold.

 
crissdee
1168500.  Sun Jan 10, 2016 3:02 am Reply with quote

Again, what they choose to call it is one thing, what it actually is, is another.

 

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