Introduction

Have you ever thought about what it would be like to live in a monochromatic world like a black and white TV screen from several decades ago? It would be a dull and boring world because color affects our emotions and allows us to enjoy the beauty of nature. Color is a great mystery and fascinating aspect of God's creation.

My motivation for this experiment is condensed in the following quote from the book Blue and Yellow Don't make Green: Michael Wilcox.

"The painter with an understanding of the fundamentals of subtractive mixing is in a position to obtain the desired results quickly and without wasting paint. Once in a position to obtain the desired results quickly and without wasting paint. Once the distinctions between the different types of contributing colour are appreciated, the painter can fully control colour mixing. Now that you have taken the trouble to actually LOOK INSIDE the paint layer in order to understand the mechanics of paint mixing, you will have laid the groundwork for quickly obtaining any desired colour." (P.50)

In order to make the colors I have in mind without wasting paint, I have decided to conduct this experiment. This experiment will help whoever wants to learn more about color mixing.

I conducted my experiment which consists of two parts; the lab experiment and theoretic study about colors. In the end, I will combine those two and draw the conclusion.

Color

"The simple fact is that we quickly forget all but the most general features of a color as soon as we look away from it, and yet, the very foundation of color mixing instruction relies on remembering the results of countless color mixes." (P.14)

There has to be a better way to know the results of color mixing besides simply trying to memorize them from the surface appearance of colors. Let's transform the color mixing into a controlled thinking process.

Prism

Issac Newton succeeded in proving that all colors are physically contained within white light by letting the white light pass through a prism. Various wavelengths that make up white light are bent at slightly different angles, therefore seperating them from their travelling companions.

Surface color

Why do surfaces reveal different colors when they are struck by the same white light? To answer that question, we need to recognize that each object is made up of atoms which are seething with invisible energy. A black surface absorbs the energy of the light. In contrast, a white surface has a molecular that rejects almost 'all color waves' equally. A blue surface absorbs nearly 'all color waves' except blue, which is reflected back to our eyes.

Inside the paint film

Pigments are tiny particles which reflect certain colors . Paint consists of tiny specks of pigment surrounded by a binding substance. Binders are the vehicle which holds the pigment particles together. Gum arabic is the binder in water colors and linseed oil is the binder in oil paints. Let's get inside the paint film to see the sequence of events.

1. The light arrives at the red (using red as an example) surface.

2. A portion of the light is reflected off the surface and remains as white light.

3. Much of the white light continues on its journey and enters the oil/ gum binder.

4. When the light reaches the pigment particles, most of it is absorbed, apart from the red portion which is reflected. Pigments absorb the majority of every other colour except their own.

5. The reflected red light either leaves the binding film directly or bounces off other pigment particles, before finally emerging from the paint film. This red light combines with the reflected white light, giving an overall brighter effect.

6. Via the eye, this information is recorded as a red 'sensation' in the observer's brain.

When oil is used as the binder, it forms a smooth film and acts as a efficient reflector of light. Gum has a slightly different effect on how colors appear on the surface, which I am going to observe in this experiment.

The reason why mixing the Three "Primary colors" leads to the statement "Blue and yellow don't make green"

Theoretically, when three PURE primary colors are mixed in equal intensities, only a tiny proportion of the light energy reaching the surface is reflected, while the rest is absorbed. The result is a very dark grey, approaching black.

In the same way, when two PURE primary colors are mixed in equal intensities, they result in a very dark grey, almost black. Why? Take the example of a PURE yellow and PURE blue. First, yellow pigment absorbs all light except the yellow. In a same way, the blue pigment absorbs all but the blue portion of the light. Mixed together, the yellow pigment absorbs all the blue light and vice-versa, therefore resulting in dark grey, approaching black.

This is why the book states "Blue and Yellow don't make Green."

So this leads to the theoretical conclusion: if the mixture of blue and yellow MAKES green, they are simply NOT PURE primary colors.

Materials and Tools

*Powdered Pigments and binders (Total 6 pigments and 2 binders)

Color wheel 1 consists of Bluish Red (alizarin), YB (centulean blue), RY(cadmium yellow) with poppy seed oil as the binder. Color wheel 2 consists of same pigments with gum arabic as the binder.

Color wheel 3 consists of YR (vermilion red), RB (Ultramarine), and BY (lead tin yellow) with poppy seed. Color wheel 4 consists of same pigments as color wheel 3, with gum arabic.

*Papers and canvas

*15-20 paint brushes

*Paper towels

*Plastic gloves and glasses for safety

*Mineral spirit and 2 beakers to clean brushes

*Colorimeter

*12 small plastic containers to keep paints

*Mirror as a place to mix paints

Procedure

Create paints by mixing pigments with binder.

For the first part of the experiment, the constant factors are the three pigments in each test as explained in "materials and tools." Variables are two sets of pigments, binder. Hypothesis is good/bad mixtures will result depending on the pigments. Binders will have an effect.

For the second part, I will make a bigger Bias-color wheel combining the six pigments from previous tests. I call those six paints bluish red (BR), yellowish red (YR), reddish blue (RB), yellowish blue (YB), bluish yellow(BY), and reddish yellow(RY). I mix them to create secondary colors that are several oranges, purples, and greens. At this point, I compare and contrast my result to "Blue and Yellow don't make Green." I use the colorimeter and record the data, so that I will gain a better understanding of color mixing. I will also do an enhancement to look for a combination of primary colors that make the darkest brown.

In the end of the experiment, I will make my own painting using those six colors.

Observations and Data

Making Paints

I started out measuring 1.5g of each pigment. It made me realize that the weight of each pigment differs. Alizarin seemed to be most powderly looking and the lightest of all, therefore needed to be mixed with more binder to make smooth paint. I planned to make a chart to record how many drops of binders each pigments required; however, soon I realized I needed to keep adding binder to keep them from drying up.

I pretty much trusted my own eyes to determine when to stop mixing paints.

The picture on the left : Six containers on the left contains poppy seed paints. Their colors are darker overall than the gum arabic paints. Poppy seed paints are a lot smoother and easier to paint with. It blended with all the pigments I used. On the other hand, some pigments took a while to mix with gum arabic. I also needed to keep adding gum arabic more often than the poppy seed because it dries a lot faster. Arizarin resisted to blending with gum arabic and remained powderlly, as you can see on the picture. ( I should have mixed some water, but I did not.)

The picture on the right : The two color wheels on the top are poppy seed paints, and the two bottom ones are gum arabic paints. When paints are applied on the paper, poppy seed paints do not appear any darker than gum arabic. I used a thin handmade paper (398g), which sucked oil out of paints and made clear spots around the painted area. When I started mixing paints, I attempted to count the drops to record how much paint I mixed, however, I had to give up the idea because the paints were too thick to be treated with dropper.

Mixing paints

I combined all the colors from small color wheels and added more. I only used poppy seed paints because they are easier to mix and apply on the paper than gum arabic.

I used the colorimeter to find out the Munsell (I only recorded the hue of Munsell because lightness and saturation depended on simply how I applied paints) and L,a,b values of the primary colors as well as some colors that particulary interested me. (I did the last two greens because they appeared to be purer green.) The result shows that I did not quite get the main hues that I wanted, but some are close. I was surprised to see that red blue had more yellow than blue.

I realized that it was difficult to make brown close to gray by mixing three primary colors. The darkest I got was mixing RB, RY, and BY. This result shows how far my primary colors are from PURE primary colors.

Conclusions

The two binders difinately affected the characteristics of paints. Poppy seed oil made smoother paint that did not easily dry up. Gum arabic overall made very sticky paints, which were difficult to handle because I had to keep adding the binder so that they would not dry up. I should have added water to make it smoother since it was supposed to be a watercolor paint. I also realized that I needed to choose the kind of papers more carefully to fit the characteristics of the binders.

None of the greens I made was close to grey/black. According to my research result from "Blue and yellow don't make green", it shows how different what I thought were the "Primary"colors are, from PURE primary colors. The difference in an intensity might have affected the result as well.What then, would Pure primary colors look like?? It is a mystery.

My purpose to gain the better understanding of color mixing was definately accomplished. I learned so many things along the process. I tried to guess how the color would turn out to be before mixing, and my guess got more accurate toward the end of the experiment. The more I did it, the more educated guesses I could make, such as RY would only make yellowish green when mixed with any kind of blue.This experiment taught me that six pigments were enough to make an varieties of colors. The way I chose those six colors for this experiment was very successful. Organizing each primary color into warm and cool colors was a great way to understand the pattern of color mixing. This experiment made the color mixing less overwhelming and easier to approach.

Links

This link is useful to research pigments.

http://webexhibits.org/pigments/

Other References

Wilcox, Michael. Blue and Yellow don't make Green. Revised edition. Cincinnati, Ohio: North Light Books, 1994.

Acknowledgements

Dr.Bordley, Mrs. Wendy.