Brilliant Colour: About Paint and Pigments

A Splash of Colour
Colour is seductive, appealing to us on both cultural and instinctual levels. Everyone responds to colour, but for artists, it’s our primary tool.
The term “artists’ quality” generally stands for the strongest, lightfast colours in the clearest, most durable binders, and while student quality paint suits basic application, colour in its most concentrated form is what really makes a painting zing!
If colour is important to you, there’s no going past professional-quality paints. Not only are Artists’ Quality colours much more concentrated, many colours are unique to artists’ quality ranges, even in a colour like white!


Single Pigments Colours
Pigment is the raw colour component of paint, and comes from many sources: some are dug from the earth, like iron oxides that make cheap and useful “earth colours”; others are complicated arrangements of elements that produce intense colours, such as Quinacridone. Obviously, it’s difficult to put much, if any, of the expensive pigments into a paint that’s primary purpose is to be inexpensive, limiting the range of colours available in “Student Quality”. Notably absent are important Cadmium & Cobalt colours; instead, mixtures of cheaper pigments are used to imitate the expensive colours (these are called “hues” or “tones”), but without the original’s clarity and strength.

Cadmium is an earth metal that became an important opaque artists’ colour in the late 19th Century. It’s expensive, so only available in Artists’ Quality ranges. It’s imitated in student ranges with a mixture of cheaper pigments, but doesn’t have the opacity or tinting strength – compare the Cadmium Red Deep Imitation (top left) with the genuine Cadmium Red Medium below it.
Cobalt colours are also very important yet expensive earth metals, which are imitated in cheaper paint ranges. Cobalt Blue as an imitation (top middle) uses white with Ultramarine & Phthalo Blue, giving a chalky look compared with the genuine Cobalt below it.
Even when using the same inexpensive pigments such as the yellow on the right, the true Artists’ Quality (lower right) uses a far greater concentration than student colour (top right).
You get far more pure colours, made from a single pigment, in the Artists’ Colours; and while important for overall luminosity, this is especially beneficial in mixing. As a rule of thumb, combining more than 4 pigments together tends to make the colour dirty, so having predominantly “single pigment” colours in a range results in cleaner, brighter mixtures.
Let’s take a quick look at how pigments are listed on a tube of paint, as generic names don’t provide an accurate colour reference, especially across brands. For instance, Helio Blue, Monestial Blue, Winsor Blue, Translucent Cyan, and Intense Blue are all names given by different manufacturers for the same colour - Phthalo Blue. For proper colour identification, we need to know the actual pigment used.
The international index for pigments has each listed as two letters followed by one to three numbers, and is easy to understand:
The first letter is always “P” which stands for Pigment. The next letter stands for the colour group: R is Red; O is Orange; Y is Yellow; G is Green; B is Blue; V is Violet; W is White; Bk is Black; Br is Brown. The number is the Colour Index name, an internationally recognized reference to all pigments.
On all the above multi-named blues, one should see the same pigment description “PB15:3 Phthalocyanine”.
If only one is listed, it’s a single pigment colour. If more than one, it’s a pre-mixed colour.


Colour Mixing
Okay, let’s see what some of these single pigment colours are, and what they can do:
Many of the standard colours we use in Artists’ Quality paints are single pigment colours – Ultramarine Blue, Lemon Yellow (Hansa Yellow Light), Cadmiums & Cobalts, but here are some equally important colours that are often overlooked:




Interference colours interfere with white light, causing a “flip-flop” effect on a white surface. Interference Violet (above left) changes between violet and green, depending on the angle it’s seen on. These strange colours don’t follow the same rules of mixing as usual colours. If you mix a violet and a green together, you’d normally get brown, but here even a very small amount of green turns the Interference Violet… green! This is because there is no violet pigment involved, rather: an interference with the wavelength of violet light. The unique effect can be accentuated by mixing these special Golden Acrylic colours with gloss gel, and they perform especially well in daylight. Using Interference Colours on a black background cancels out the white light and they no longer flip-flop, instead becoming intensely iridescent. This also happens when black paint is added to our mixture (above far right).
We can’t help but seek out new colours that will inspire and excite our artistic sensibilities. Golden have put together a couple of teaser packs this year – Provocative Yellows and now Divergent Reds – with another to follow in the New Year. They contain three useful but little known colours that hopefully will expand and become permanent fixtures on your palette! The Divergent Reds are shown below.  

 

Bearing in mind that not only does everyone have different coloured skin, but the skin colour on different parts of the body are also diverse, here is a base flesh-tone that can easily be adapted. Mix Translucent Red Brown with Zinc & Titanium Whites, plus a bit of Chromium Oxide Green Brilliant (or Viridian in Golden) to stop it going too pink – this is perfect for pakeha tones. For Pacific tones, try adding Ultramarine Blue and hardly any white. Asian tones are more diverse than any, so you can try combinations of these, and the addition of earth tones, such as Yellow Ochre or Naples Yellow.
In the 19th Century, when the mysteries of creating colour were finally exposed, a popular recipe for painting skies was to add Cobalt Blue to white, and then adjust with Ivory Black. This is very effective for softer sky tones, but many artists want a brighter tone for New Zealand skies, and Phthalo Blue plus Ultramarine added to white provides a much stronger blue.


Golden’s Virtual Colour Mixer
Taking the guess-work out of colour mixing, Golden have created their Virtual Colour Mixer so you can combine up to three colours from any of their colour ranges, in any proportion, and see the result on screen. You can even build up a file of your favourite mixtures for future reference. This is a great way to try before you buy! http://www.goldenpaints.com/products/mixer/

Lightfastness 


Everyone has seen the negative effects of sunlight on low-lightfast colours, especially in bright fabric or printed matter. Light also degrades materials - wood and plastics become brittle, newspaper turns yellow. Works of art, however, are supposed to be long lived, with colours whose brilliance and luminosity remain unimpaired for many years.
Artists’ Quality colours are made to last. Even in a weak 1:10 dilution, the Aerocolor Liquid Acrylic (above top) has remained relatively unchanged after exposure to strong, direct sunlight for six months. The student quality ink below it (at full strength) has become a shadow of its former self in the area that was left exposed. The New Zealand sun is particularly damaging, and although this is not an issue when working on studies or learning exercises, it’s a disaster for a finished piece of art.  

Change of Colour
Colour speaks to us directly, and is one of our primary tools for making art. The dialogue we have with it is never-ending, as a colour’s character is ever changing. All paint has its colour affected by at least the following:

1. The pigment vehicle, whether oil, acrylic or water, wet or dry;1. The pigment vehicle, whether oil, acrylic or water, wet or dry;2. The surface sheen – gloss increases the depth, matte flattens it;3. Film thickness – especially noticeable with translucent colours;4. Concentration of colour;5. The surface – whether it’s rough, smooth, absorbent or not;6. The light – artificial or natural, weak or strong.

 

 

Staff Picks
Peter Smith, Store Manager at our Christchurch store, gives you his secret (no longer!) mixture for the missing Indigo you always wanted from Golden Acrylics: Golden Cobalt Violet Hue, Phthalo Green BS and Carbon Black. Try it out on the Golden Virtual Colour Mixer to get the proportions just right.
“You know what they say about artists who use indigo, don’t you,” Peter grins. He’s full of helpful advice, so to find out “what they say” (I have no idea), pop into the store in Southwark Street!
Indigo is the talk of Albany store too – James has always loved working in deep blues. “It must be my English sensibilities,” he says, “The way light is absorbed, like velvet. I love that indigo was a natural product; it has a mellow mystery about it.” He chooses indigo in Horadam Watercolours and Norma Professional Oilcolour.
Albany Manager Kate England calls Violet Dark Norma Professional Oilcolour “stunning and sexy – its transparency gives it so much depth. I like mixing it with black to get really concentrated darks, and with white for intense mauves. As a single pigment colour, it mixes well with everything!”
Dark tones are favoured in Symonds Street, too. Manager Johl Dwyer loves Schmincke Aerocolor’s Phthalo Green “transparent for depth and a single pigment for great mixing possibilities.” His favourite mix? “You can get a great Cobalt Teal colour by combining the Phthalo Green with Turquoise Blue and white. It’s also great for shading,“ says Johl, “but is difficult to get out of the carpet!”
So that’s what’s meant by “a splash of colour”!

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