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How to get primary (C,M,Y) emulsion paint, e.g. Dulux?
Hi,
I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB for computer monitors. The thing is, I need the colours to a high degree of accuracy. I understand that conversion between the Dulux/ICI codes (or the NCS ones from which they are scrambled) and RGB/CMY codes is not publicly available, so what I will do is get a printer to print out primary C, M, and Y and then take them along to somewhere like B&Q to be scanned with a colour meter. However, I suspect that there may be a big gap between the required colours and the best available matches, since Dulux/ICI probably don't want to encourage people to mix paint. Any advice would be welcome. Simple question really - how to get pots of primary-colour emulsion paint! Many thanks. Cheers, Chris |
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"Chris Nellist" wrote in message ... Hi, I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB for computer monitors. The thing is, I need the colours to a high degree of accuracy. I understand that conversion between the Dulux/ICI codes (or the NCS ones from which they are scrambled) and RGB/CMY codes is not publicly available, so what I will do is get a printer to print out primary C, M, and Y and then take them along to somewhere like B&Q to be scanned with a colour meter. However, I suspect that there may be a big gap between the required colours and the best available matches, since Dulux/ICI probably don't want to encourage people to mix paint. Any advice would be welcome. Simple question really - how to get pots of primary-colour emulsion paint! Johnson and Manders outlets mix paints to any colour you like and will do them to BS numbers as well. So if you can find the number of magenta etc you could be in luck. I can't see a specific match here but you may be in luck http://www.indfinspec.demon.co.uk/bs...lour_chart.htm A bit of advice on matching here http://www.pra.org.uk/technical/test...icalvisual.htm A range of BS numbers that mean nothing to me here http://www.sandtextrade.co.uk/col-bsrange.htm -- Malc |
#3
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Chris Nellist wrote:
I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB Or secondary colurs even ;-) Not sure if it helps, but Johnstones paint shops will mix Leyland colours to any spec you want. -- Cheers, John. /================================================== ===============\ | Internode Ltd - http://www.internode.co.uk | |-----------------------------------------------------------------| | John Rumm - john(at)internode(dot)co(dot)uk | \================================================= ================/ |
#4
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John Rumm wrote in message ... Chris Nellist wrote: I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB I don't think it's as simple as that with paint because the colours don't exist in pigment form. IIRC geranium red, sky blue, and buttercup yellow are the perfect primaries. Emulsions are all pastel shades anyway so, for a start, you can't get black. |
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"stuart noble" wrote in
: John Rumm wrote in message ... Chris Nellist wrote: I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB I don't think it's as simple as that with paint because the colours don't exist in pigment form. Not sure I understand you here. They exist in ink. I will be happy with 'very close' matches. IIRC geranium red, sky blue, and buttercup yellow are the perfect primaries. Depends on what you need. Physiologically a green hue would also be included. I want to use the hues defined in HTML as 0/255/255, 255/0/255, and 255/255/0. I am quite surprised that there aren't more people who buy pots of these three colours and try their hand at mixing up what they want Emulsions are all pastel shades anyway so, for a start, you can't get black. Don't know where you get this idea from. Dulux sell emulsions in dark shades and indeed in black. I don't know how 'pure' a black it is. Chris |
#6
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Chris Nellist wrote:
I am quite surprised that there aren't more people who buy pots of these three colours and try their hand at mixing up what they want I think "mixing" as in with paint, is a different kettle of fish to CMYK printing where you are not mixing but relying on the eye to integrate colours in close proximity to perform subtractive colour mixing. (You only need look at the huge number of pigment tubes that are present on a paint mixing machine to realise that it's not as simple as printing!) -- Cheers, John. /================================================== ===============\ | Internode Ltd - http://www.internode.co.uk | |-----------------------------------------------------------------| | John Rumm - john(at)internode(dot)co(dot)uk | \================================================= ================/ |
#7
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Chris Nellist wrote:
Depends on what you need. Physiologically a green hue would also be included. I want to use the hues defined in HTML as 0/255/255, 255/0/255, and 255/255/0. I am quite surprised that there aren't more people who buy pots of these three colours and try their hand at mixing up what they want Umm, there's a bit more to colour perception than you seem to acknowledge, Chris. For a start, the HTML "specs" you mention aren't in any "standardised" colour space - they'll give whatever the display device - typcially a CRT or LCD screen - happens to give when driven with (f'r example) "full" Red & Green for the 255/255/0 case, which will be something pretty yellowish; but will appear quite differently on different screens - and different again when printed on a colour printer. Secondly, for paint mixing you're doing "subtractive" mixing, rather than the additive, and the way particular pigments interact when subtracring depends (and I'm no colour chemist, not even an armature ;-) on a lot more than the absorbtion spectrum of "the" pigment (scare quotes because there's typically more than one pigment involved anyway) - I'd expect that the grainsize of the pigment, for example, would make quite a difference in how it interacted with other pigments. Pragmatically, I'd expect you'd get best results for a given colour which the existing "mix-when-you-buy" either don't give you or you feel are overpriced by buying something close, and small pots of the colours you believe necessary to pull the overall colour in the direction you want - from the same mfr, natch, to try to get maximum compatibility in the other components of the paint. But far be it from me to discourage experimentation! Stefek |
#8
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Chris Nellist wrote in message ...
Hi, I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB for computer monitors. The thing is, I need the colours to a high degree of accuracy. I understand that conversion between the Dulux/ICI codes (or the NCS ones from which they are scrambled) and RGB/CMY codes is not publicly available, so what I will do is get a printer to print out primary C, M, and Y and then take them along to somewhere like B&Q to be scanned with a colour meter. However, I suspect that there may be a big gap between the required colours and the best available matches, since Dulux/ICI probably don't want to encourage people to mix paint. Any advice would be welcome. Simple question really - how to get pots of primary-colour emulsion paint! Many thanks. Cheers, Chris Chris, offset inks are transparent and normally used on white paper. Samples are in Pantone swatch books, either Pantone Solid or Pantone Process. No need to print samples by a printer. The Lab values for any Pantone Solid or Process ink can be found by Photoshop or by measuring directly in a swatch book by an instrument. The Lab values are not shown in the swatch books. European inks are not exactly the same as US inks. Reference viewing light is D50. No problem to find the few Lab numbers, but the model has to be defined (Pantone Solid, Pantone EuroScale Coated, for example). Paints (varnishes) are opaque, not defined by Lab and viewing light may be D65 (here I´m not sure about). I didn´t find any cross-reference, but I would recommend to have a look at the RAL system (Google: RAL Colors): e.g. http://www.inver.it/liquid/ral.html Some thousands of RAL mixtures are already defined and available in swatch books. Perhaps it is sufficient to choose the nearest RAL color by swatch book comparison. Just for fun I´ve tried to find a company which mixes paints as specified by Lab - no success so far. Best regards --Gernot Hoffmann |
#9
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On 2 Nov 2004 13:15:57 GMT, Chris Nellist
wrote: "stuart noble" wrote in : John Rumm wrote in message ... Chris Nellist wrote: I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB I don't think it's as simple as that with paint because the colours don't exist in pigment form. Not sure I understand you here. They exist in ink. I will be happy with 'very close' matches. IIRC geranium red, sky blue, and buttercup yellow are the perfect primaries. Depends on what you need. Physiologically a green hue would also be included. I want to use the hues defined in HTML as 0/255/255, 255/0/255, and 255/255/0. I am quite surprised that there aren't more people who buy pots of these three colours and try their hand at mixing up what they want Emulsions are all pastel shades anyway so, for a start, you can't get black. Don't know where you get this idea from. Dulux sell emulsions in dark shades and indeed in black. I don't know how 'pure' a black it is. Chris We mix our own colours, and have had a few learnings on the way. From experience - Its not nessecarry to use the same brand, unless its some form of plastic emulsion - start with a color thats neer what you want - buy piles of the matchpots from B&Q when they are going cheep - buy any cheep colors from B&Q when they are end of line Mix all you need in one go !!!!! Have Fun Rick |
#10
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You are correct in saying I don't think it's as simple as that... but
not for the right reasons. a. Cyan, Magenta and Yellow are not paint primary colours but transparent printers' ink primaries and rely on overlay not pre-mixing for the effect. Paint primaries are red, blue and yellow and, in emulsion paint, are opaque. b. The colours Chris wants are available from artists' suppliers in acrylic emulsion. c. Geranium red, sky blue, etc. are manufacturers' names for certain colours and are not consistent. d. All colours are available in emulsion, as is black. Chris, if you could let me know what you want to do with these colours I can probably advise. Alan Taylor "stuart noble" wrote in message ... John Rumm wrote in message ... Chris Nellist wrote: I would like to get some pots of ordinary emulsion paint in the primary colours, i.e. cyan, magenta, and yellow, as used by printers and as easily specifiable in RGB I don't think it's as simple as that with paint because the colours don't exist in pigment form. IIRC geranium red, sky blue, and buttercup yellow are the perfect primaries. Emulsions are all pastel shades anyway so, for a start, you can't get black. |
#11
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"Jo [actually Alan] Taylor" writes:
You are correct in saying I don't think it's as simple as that... but not for the right reasons. a. Cyan, Magenta and Yellow are not paint primary colours but transparent printers' ink primaries and rely on overlay not pre-mixing for the effect. Paint primaries are red, blue and yellow and, in emulsion paint, are opaque. Alan Taylor made this same argument nearly a month ago here. Eventually he made some example images available on the Web; unfortunately viewing them required one to be a member of the Yahoo BritArt group. I have rehosted them with his commentary; see http://www.alumni.caltech.edu/~mjackson/color.html. He's got some further words that should accompany the images, but I don't have access to my alumni account from work so will leave it to him to make any additional points here. -- Mark Jackson - http://www.alumni.caltech.edu/~mjackson Learning without thinking is useless. Thinking without learning is dangerous. - Confucius |
#12
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"Mark Jackson" wrote in message ... "Jo [actually Alan] Taylor" writes: You are correct in saying I don't think it's as simple as that... but not for the right reasons. a. Cyan, Magenta and Yellow are not paint primary colours but transparent printers' ink primaries and rely on overlay not pre-mixing for the effect. Sorry to ask this at this point, but does it make any difference as to which colour is put down first? Paint primaries are red, blue and yellow and, in emulsion paint, are opaque. Can this be explained to me? I must add that I am some what colour blind here. I was diagnosed as red green colour blind as a child and it has haunted me since. And here is me, interested in photography :-) I get along though ;-) My wife tells me what I have done wrong in PhotoShop, but I wish I did not have to depend on her. Alan Taylor made this same argument nearly a month ago here. Eventually he made some example images available on the Web; unfortunately viewing them required one to be a member of the Yahoo BritArt group. I have rehosted them with his commentary; see http://www.alumni.caltech.edu/~mjackson/color.html. I looked at that, but found some of the darker colours hard to define :-((((( Dave |
#13
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"Dave" wrote in
: Sorry to ask this at this point, but does it make any difference as to which colour is put down first? Yes. For a simple three-colour run, yellow is often the topmost ink as it has the least capacity for hiding the lower inks. Printers have different views of the optimum order. But with a large modern press, there might be ten or more actual printing stations each laying down a different ink. (Not all inks will necessarily be used for all jobs.) Changing the order from run to run is not feasible. So there is probably some order that is regarded as standard for a particular printing process/set of inks/press. When making colour plates, the dot pattern is produced at different angles for each ink (up to a point, difficult with large numbers of inks) so that there is less chance of a later ink completely obliterating an earlier one. The differing angles basically ensure that the dots in one layer cannot perfectly align with the dots in another layer. This lessens the criticality of the printing order. Paint primaries are red, blue and yellow and, in emulsion paint, are opaque. Can this be explained to me? I must add that I am some what colour blind here. I was diagnosed as red green colour blind as a child and it has haunted me since. My partner's son is also red-green, umm, confused. Hence we have looked around to try to understand the issues. If you have never seen it, http://www.vischeck.com/ is quite amazing. Also, http://www.tsi.enst.fr/~brettel/colourblindness.html -- Rod www.annalaurie.co.uk |
#14
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Rod Hewitt writes:
"Dave" wrote in : Sorry to ask this at this point, but does it make any difference as to which colour is put down first? Yes. This is true of xerographic toners as well. When making colour plates, the dot pattern is produced at different angles for each ink (up to a point, difficult with large numbers of inks) so that there is less chance of a later ink completely obliterating an earlier one. The differing angles basically ensure that the dots in one layer cannot perfectly align with the dots in another layer. This lessens the criticality of the printing order. Actually, I believe this has nothing to do with layered combinations depending on printing order - after all, shifts in relative dot position can't reverse the order, only move from dot-on-dot to dot-off-dot. And *that's* the key - the color you get in these two cases (even for standard, transmissive inks) will be different, certainly because of overlap in the absorption spectra and possibly because of physical effects changing the uptake of the second color. -- Mark Jackson - http://www.alumni.caltech.edu/~mjackson Learning without thinking is useless. Thinking without learning is dangerous. - Confucius |
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Gernot Hoffmann wrote:
Just for fun I´ve tried to find a company which mixes paints as specified by Lab - no success so far. I am prety sure when I had some paints mixed that teh final color was expressed not only as a mixture of various pigments in a base, but also with CMYK type values as well. Best regards --Gernot Hoffmann |
#16
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c. Geranium red, sky blue, etc. are manufacturers' names for certain colours and are not consistent. No, the actual colours of geraniums, the sky, and buttercups are reckoned to be the perfect paint primaries, but there are no corresponding pigments in the real world. d. All colours are available in emulsion, as is black. Compare it to an oil base black and you will see that it is, at best, grey. Practically all blacks tend towards blue, which is why ICI used to charge the earth for a perfect black dye. If the perfect primaries existed, you could mix them in equal parts and get black |
#17
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No, brown, if you are talking about paint. Any pair of complementary colours
in paint produce a brown with a particular bias depending upon the primary employed. Black is not a colour but an extreme of tone. -- regards, alan http://groups.yahoo.com/group/BritArt/join Click to subscribe to BritArt If the perfect primaries existed, you could mix them in equal parts and get black |
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Mark,
This is great - our artist friend's Red, Blue Yellow primaries are Quinacridone - a blue-shade red (also known as quinacridone magenta), Pthalocyanine Blue - the standard SWOP cyan, and azo Yellow (the SWOP yellow). So, in fact, his standard RBY primaries are in reality CMY. End of discussion. "Mark Jackson" wrote in message ... "Jo [actually Alan] Taylor" writes: You are correct in saying I don't think it's as simple as that... but not for the right reasons. a. Cyan, Magenta and Yellow are not paint primary colours but transparent printers' ink primaries and rely on overlay not pre-mixing for the effect. Paint primaries are red, blue and yellow and, in emulsion paint, are opaque. Alan Taylor made this same argument nearly a month ago here. Eventually he made some example images available on the Web; unfortunately viewing them required one to be a member of the Yahoo BritArt group. I have rehosted them with his commentary; see http://www.alumni.caltech.edu/~mjackson/color.html. He's got some further words that should accompany the images, but I don't have access to my alumni account from work so will leave it to him to make any additional points here. -- Mark Jackson - http://www.alumni.caltech.edu/~mjackson Learning without thinking is useless. Thinking without learning is dangerous. - Confucius |
#19
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No brown? What happened to Sienna or Burnt Umber? Those used to be in
every paint palette set in the art stores that I visited and they are definitely brown. Danny "Jo Taylor" wrote in message ... No, brown, if you are talking about paint. Any pair of complementary colours in paint produce a brown with a particular bias depending upon the primary employed. Black is not a colour but an extreme of tone. -- regards, alan http://groups.yahoo.com/group/BritArt/join Click to subscribe to BritArt If the perfect primaries existed, you could mix them in equal parts and get black |
#20
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Not quite. These are the names given to a particular range of paints by a
particular manufacturer. I have the same colours by other manufacturers and they carry different names and different ingredients. Furthermore, the range in question is from the lower end of the students' quality range which, by definition, contain the minimum of pigment and the maximum of body. If you read the text alongside the samples you will see the colours were chosen solely on the fact the word 'Primary' occured on the tube. The next task is to create a similar test using top of the range artists' colours and make a comparison. More importantly, transparent printers' inks are pale colours, each with a covering capacity (opacity) of approximately 33%. They are dependant on the reflected white light from the paper for their success. Magenta and Yellow (strictly pale yellow) printers' inks, overlaid on white paper will produce a very good red. Magenta and Yellow paint, mixed on a palette, will produce a pale orange. Cyan and (pale) yellow transparent ink will produce a good green (33% opacity on 33% opacity = 66% opacity). The same colours in paint will produce a pale green. A magenta/cyan ink overlay creates a strong blue whereas a similar paint mix produces a pale purple. The three colours that cannot be made by mixing any paint are red, blue and yellow - the defining factor in establishing the primaries within the RBY system. -- regards, alan http://groups.yahoo.com/group/BritArt/join Click to subscribe to BritArt "Danny Rich" wrote in message et... Mark, This is great - our artist friend's Red, Blue Yellow primaries are Quinacridone - a blue-shade red (also known as quinacridone magenta), Pthalocyanine Blue - the standard SWOP cyan, and azo Yellow (the SWOP yellow). So, in fact, his standard RBY primaries are in reality CMY. End of discussion. "Mark Jackson" wrote in message ... "Jo [actually Alan] Taylor" writes: You are correct in saying I don't think it's as simple as that... but not for the right reasons. a. Cyan, Magenta and Yellow are not paint primary colours but transparent printers' ink primaries and rely on overlay not pre-mixing for the effect. Paint primaries are red, blue and yellow and, in emulsion paint, are opaque. Alan Taylor made this same argument nearly a month ago here. Eventually he made some example images available on the Web; unfortunately viewing them required one to be a member of the Yahoo BritArt group. I have rehosted them with his commentary; see http://www.alumni.caltech.edu/~mjackson/color.html. He's got some further words that should accompany the images, but I don't have access to my alumni account from work so will leave it to him to make any additional points here. -- Mark Jackson - http://www.alumni.caltech.edu/~mjackson Learning without thinking is useless. Thinking without learning is dangerous. - Confucius |
#21
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On Tue, 2 Nov 2004 08:56:40 -0000, "stuart noble"
wrote: Emulsions are all pastel shades anyway so, for a start, you can't get black. We regularly buy black emulsion for theatrical "sets". -- Frank Erskine |
#22
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No, brown, if you are talking about paint. Any pair of complementary colours
in paint produce a brown with a particular bias depending upon the primary employed. Black is not a colour but an extreme of tone. regards, alan Alan, could you extend the generalization above to include any two 'complentary" primaries to inks? For instance, a PANTONE 185 which is red in appearance and a PANTONE 347 which is green in appearance. Could you say that mixing these two inks will yield a brown? Roger Breton |
#23
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More importantly, transparent printers' inks are pale colours, each with a
covering capacity (opacity) of approximately 33%. They are dependant on the reflected white light from the paper for their success. Magenta and Yellow (strictly pale yellow) printers' inks, overlaid on white paper will produce a very good red. Magenta and Yellow paint, mixed on a palette, will produce a pale orange. Cyan and (pale) yellow transparent ink will produce a good green (33% opacity on 33% opacity = 66% opacity). The same colours in paint Alan, how do you operationalize 'covering capacity' or opacity? Do I average out the spectral reflectance from 400 to 700nm out of my spectrophotometer? Roger Breton |
#24
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Hello. Not without knowing exactly to which inks you are referring. I
checked all the Pantone range and only found matching numbers red and green in 'Pantone Uncoated'. 185 red is close to pure - just a hint of yellow - and the 347 green has a strong grey content. But, if such colours existed in opaque paint, it is most likely they will produce a brown. A lot depends on the nature of the paint or ink. For example, in artists acrylic most manufacturers produce different ranges - school, student and artist qualities being typical. The 'school' quality is cheap and the 'artist' quality anything up to four times as expensive with quality of pigment and amount of body (chalk or carbon) being the important factors. An artist quality primary blue mixed with a similar quality yellow will give a very good, clean green. The same colours in school quality will be much greyer (or 'muddy') when mixed. If, in referring to ink, you mean drawing inks and not standard printers' process colours then, depending upon the quality of the inks, such a red and green would produce brown. Opaque silk screen ink works just like paint in that it is mixed before application and does not rely on transparent overlay as in the process CMYK system. I think a lot of the confusion is eliminated once it is understood that three distinct colour systems exist - RBY (paint, opaque), RGB (light, transparent) and CMYK (printers process inks, also transparent). Each has its own set of primaries, secondaries and complementaries and mixes within any system create different results. A standard six colour RBY colour wheel will always show green opposite red and the two, when mixed, will produce a brown with a red bias - 100% red + 50% blue + 50% yellow - just as a blue/orange mix will produce a brown with a blue bias. I would be happy to discuss this further off list if you want to contact me. -- regards, alan http://groups.yahoo.com/group/BritArt/join Click to subscribe to BritArt "Roger Breton" wrote in message ... No, brown, if you are talking about paint. Any pair of complementary colours in paint produce a brown with a particular bias depending upon the primary employed. Black is not a colour but an extreme of tone. regards, alan Alan, could you extend the generalization above to include any two 'complentary" primaries to inks? For instance, a PANTONE 185 which is red in appearance and a PANTONE 347 which is green in appearance. Could you say that mixing these two inks will yield a brown? Roger Breton |
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