Color mixes to make your head explode, or, green + red = purple?

[Pingo]

Color theory is a good foundation for painting, but it doesn't deal with some of the surprising and fun things paint can do. Color theory is a limited approximation that works with light, but not really with paint, because in paint there are no colors, there is only chemistry.

 

And that's a good thing.

 

Pigments are chemical substances chosen for their optical properties, but they are more than just their optical properties. And you can do a lot with them. Any two colors can be blended in a myriad of ways: physically mixed, layered one over the other, layered the other over the one, blended optically with tiny brushstrokes -- and each method can produce an entirely different effect and apparent color, just from two original paints.

 

As many of you are aware, in my day job I'm a fine artist and when painting minis I tend to mix my own colors rather than rely on premixed miniatures paints.

 

In a few threads people have asked me about various color mixes, so I figured I'd pull some of them together in this thread to make them (hopefully) easier to find.

 

***

 

In my current WIP thread, "Pingo Builds a Boat", I said

 

...I mixed up some transparent deep purple using phthalo green (that's right, green, and I'd be glad to talk about color mixing if anyone's interested, because there's not a speck of blue on that deck) and quinacridone magenta...

 

...

 

Oh, and since I was already using purple, I threw some paint on a couple of not-Illithid figures I have which will be needed in-game later (one from Reaper and one classic old Ral Partha). Nothing gives a terrific Illithid "greenish-mauve" like a purple mixed from green and red....

 

Well, naturally I got some questions.

 

Phthalo green (copper phthalocyanine) is a really intense, pure, blueish green. It's related to phthalo blue, which is also intense and pure and close to a printer's cyan. They are related, but phthalo green is clearly and obviously green when you look at it, and phthalo blue is blue.

 

When I mixed my purple, I didn't just mix phthalo green with any old red (certainly not the flame orange reds they give to unwary kindergarteners). I mixed it with quinacridone magenta, a deep hot pink-red which is close to a printer's magenta.

 

A more muted green, or a yellower one, or a more orangey red would have produced something a lot more brown and mucky. Mixed colors are always more subdued than the colors you start with.

 

But both phthalo green and quinacridone magenta are very pure, intense colors. Even a mix of them is still pretty bright.

 

This is one of the palettes I have been using to paint the boat in the other thread:

 

The phthalo green is in the lower left corner. It's very dark full strength but thinned down even a little becomes an intense emerald green. There's a tiny blob of quinacridone at the top between the two different reddish browns. You can see how the color mix between them snaked out through blue to violet (mixed-in white makes the color easier to see, although I did it for painting reasons originally).

 

Yes, that's right. Not only can you mix green and red to make purple, you can mix a blue from green and red.

 

Isn't color mixing fun?

 

To show things a little more clearly, I've laid out some paint on waxed paper over white paper towels.

 

First, this is phthalo blue (which we're not using at all, but I'm including it to show how it is different from phthalo green) at the top. Below it is phthalo green, and to the right is quinacridone magenta. In each case I've used water to thin the paint out to the right so you can see how transparent layers of it look, and I've mixed a little blob of white paint with each color at its top left so you can see how it looks mixed. (Note that the white-mixed colors are already less intense than even the pale thinned paint)

 

To get an idea of the vividness of the colors, here's that palette amongst my painting set-up.

 

And here is a good big blend from phthalo green at the left to quinacridone magenta at the right, with a few spots picked out for mixing with white to show color undertones.

 

Note that all of the mixes are considerably darker than the original colors, even the one with only a touch of red added to the green, but that they don't really get close to the black color theory says they should become. However, note that that is a pretty nice blue right in the middle.

 

The violet I used on the boat was more from the right third region, where the mix is dominated by the quinacridone and the sample blended with white shows clearly a lavender purple.

 

Finally, here are a couple of minis (still works-in-progress) painted with this green-and-red mixed purple.

Illithids are described as having "greenish-mauve" flesh, and by tipping the mix a little this way and that they can have skin that is both violet and green harmoniously. Oh, and the trousers on the one on the right are painted with the mixed blue from above.

 

 

[buglips*the*goblin]

Nice walkthrough. I noticed the red + green makes purple thing once or twice, along with some other weird stuff. The mad scientist part of the hobby is a goodly bit of the fun, and why in my WIPs I encourage people to experiment and see what happens.

[Pragma]

I am also a total colour theory nerd, but coming from the other side. I used to work in computer graphics, and I know a bit about the math and physics of colour.

So naturally at one point I wrote a little python script that would take a target colour in rgb and spit out a mixing recipe based on the colours you have. I used it to generate paint mixing recipes for the mini in my avatar from the paints from learn to paint kit #2. It did okay, but there were a lot of interesting subtleties that I wasn't able to take into account.

1. The way a paint mixes depends not only on its colour, but also its opacity. This means that two colours can look exactly the same out of the pot, but behave totally differently when mixed.

2. Paint mixing is non-linear. The result you get from mixing two paints might not be "between" the colours of your initial paints. Pingo gave some really wild examples of this, but yellow + black = green is a common example.

3. Even though we only see a 3-dimensional space of colours (some lucky people see 4) the space of colours is actually infinite-dimensional. This means that in order to know how paints will mix you need more information than your eyes or a camera can give you. You would need some kind of spectrometer to measure the colour properly.

It's cool that you have found some really cool examples of these things by experimenting.

I thought about sharing the script, but I figured that not many people would be interested and have a working python installation. I also thought about doing it in html, but I don't really know how.

[Baugi]

Am I right in thinking that Reaper's (now out of production) Clear Viridian is phthalo green, then? I remember being surprised at how cool a green it was when I got a couple bottles recently.

[evhorne969]

There's a GREAT book that explains all of the science behind the color mixes you're getting. It totally blew my mind the first time I read it and I Gauron-teee it will transform the way you think about and apply color theory. It's by Michael Wilcox and its called Yellow and Blue don't make Green. Here's a link if you're interested.

 

http://www.amazon.com/gp/product/0967962870?ie=UTF8&force-full-site=1&ref_=aw_bottom_links

 

Gene

[Pingo]

Am I right in thinking that Reaper's (now out of production) Clear Viridian is phthalo green, then? I remember being surprised at how cool a green it was when I got a couple bottles recently.

As far as I know that's correct. Apparently it didn't sell well enough to be kept in production.

[trystangst]

I remember the first time someone told me I could use red to darken green, or green to darken red. I looked at them like they were nuts. But it worked.

[Sanael]

Pingo, thanks for all this. I still have a bottle of Viridian from RMS, so I'm going to play with it a bit to see what happens. I'm still a color theory noob in a lot of ways, but this sounds like it'll be fun.

[chaosscorpion]

Pingo Thank you. It totally breaks my rules for how I see things. I come from the school that red + yellow = orange, yellow + blue = green, and blue + red = purple. I understand chemistry from my background in maths and sciences as an engineer. I guess it is time that my art and science mix and make magic.

 

Looks like I have some more reading to do. On anther thought my airbrush rig should be ready for use this weekend. May have to practice some of the learning on the boards.

[Pingo]

Here's another unexpected color combination, and a really versatile one.

A couple of months back I posted a mini in Show Off, Dionne the Vampire from Hasslefree. She was a bit of an experiment in monochrome, and Darsc Zacal started everything which led to this thread by asking

Stupid question time, but what colours did you use to paint the overcoat? I can't quite tell from the pic.

The color in question was a dark neutral grey, almost black, which I had mixed from burnt sienna and ultramarine blue. It's been my favorite shadow mix since forever, and a source of an infinite number of subtle greys which slowly shade from cool to warm.

Here's how I replied at the time:

It's my favorite neutral mixed grey and painting secret: burnt sienna mixed with ultramarine blue, lightened as needed with white.

Perfectly balanced, those two colors produce a semi-transparent naturally matte near-black that makes richer and more subtle shadows than straight black. With white added it becomes a nuanced neutral grey.

It's not quite perfect for glazing on minis scale, because even high quality ultramarine blue has a gritty texture in washes, but it makes for lovely deep shadows.

The mix can be tilted towards either brown or blue and mixed with white to make warm or cold greys which harmonize perfectly with the neutral one and blues and browns that also go together naturally.

I have painted entire paintings using only those three colors. I don't know that I would recommend that, but it is an interesting exercise.

 

Ultramarine blue is very different from the phthalo blue shown briefly in the earlier post on this thread. Phthalo is deeply transparent, dark cyan blue, and very, very strong (i.e. it tints other colors easily even with a small amount), whereas ultramarine blue is translucent, more of a pure intense deep sky blue and less greenish than phthalo blue, and is nowhere near as strongly tinting. It also dries to a naturally matte finish, which can be useful, and depending on the manufacturer, can have a sulphurous smell uniquely its own.

 

Burnt sienna is a natural earth pigment colored by iron oxides. Its color varies a bit depending on the source (it is clay dug up from the ground and toasted), but overall it's a rich red-brown that in thin washes turns a beautiful flamelike orange. I haven't confirmed this, but I believe Reaper sells burnt sienna as Chestnut Brown.

 

Here is the mix, done the same way I did the earlier one above, on waxed paper over white paper towels, thinned with water towards the right, mixed with a bit of white at the top left, and then mixed in a wide band with dabs of white to show a few points along the shading.

Note that the paints mixed with white are much paler than in the earlier example. I wasn't totally scientific in measuring exact amounts of white, but this gives a general sense of how much lower their tinting strength is.

 

Without any white added, these colors are rich and transparent. Towards the middle left there is almost a black grape purple color which I think would work really well for an organic-looking dark elf flesh. In fact, all of the greys and blacks mixed with these have a certain organic look.

 

This is the mini I painted for that earlier thread. Her trench coat is painted with mixes of ultramarine blue and burnt sienna with a bit of white to lighten them. Compare it to her jumpsuit, which is pure black and white, and you can see how much more interesting the mixed near-black is than the pure black pigment.

Edited June 26, 2013 by Pingo

[MonkeySloth]

You really should just write "Pingo's guide to painting Miniatures" and let us all throw money at you.

[Anne]

There's a great book for color theory study also called: Color and Light: A Guide for the Realist Painter, by James Gurney, very helpful. One of the books I keep on the close shelf near the paint table. A linkie if you like:

http://www.amazon.com/Color-Light-Guide-Realist-Painter/dp/0740797719/ref=sr_1_1?s=books&ie=UTF8&qid=1372283618&sr=1-1&keywords=color+and+light

[Talae]

There's a great book for color theory study also called: Color and Light: A Guide for the Realist Painter, by James Gurney, very helpful. One of the books I keep on the close shelf near the paint table. A linkie if you like:

http://www.amazon.com/Color-Light-Guide-Realist-Painter/dp/0740797719/ref=sr_1_1?s=books&ie=UTF8&qid=1372283618&sr=1-1&keywords=color+and+light

As in the Dinotopia guy?

[CashWiley]

I'm a visual thinker, so this page from the interesting Blue and Yellow Don't Make Green was my 'aha' moment.

 

 

 

 

It helped me to stop thinking of colors as 'red' and see things as more of red/orange or red/violet. Less big chunks of the spectrum and more subtle gradations. It's a really fun past time to just look at colors and try to figure them out. Browns and greys still stymie me.

 

Talae, yes. I have that book and consider it essential. He's also got a couple more that are excellent.

[Talae]

That image is from the linked book?