What You Should Know About Oil Paints.  By Don Finkeldei: This article is about the qualities and properties of paint ,student grade vs. artist grade, unexpected results of mixing paint with different properties, mixing different brands of paint, and transparent vs. opaque.

I was fortunate early in my painting career to understand the importance of this seldom discussed topic in workshops. I stick with one brand, few colors (Limited Palette) and the highest quality artist grade paint I can afford. The result is that I learned how to quickly mix what I need and be exact with the result everytime - and it accelerated my learning curve tremendously.

Common Mistakes students and even experienced painters make.

1. Buying student grade, low series cheap paints thinking it saves money in the long run and the painting will not be affected much. Nothing could be farther from the truth and in fact, as I show below, you can get strange and wierd results when mixing these inferior paints with other inferior paints or even with high quality paints. Student grades and hues are generally very weak and they don't go nearly as far as artist grade paints so you actually will end up paying more in the long run. Student grade paints are for getting your feet wet only.
2. Switching brands of paint often and mixing different paints between manufacturers. Each manufacturer has slightly different manufacturing teqniques with different pigment saturations, supension vehicles and chemical elements. Every time an artist switches manufacturers a new learning process has to happen to understand the mixing qualities and quantities and proportions needed to get the right hue, value and saturation you need for the next stroke.
3. Using a wide variety extended palette consisting of vastly different types of pigments. The list of chemical compounds used in paint is in the thousands. Cobalts, cadmiums, manganese, pthalocyanides, napthols, bariums - and the list goes on and on. Each compound has different chemical properties, molecule sizes, opaqueness, transparency, and light fastness. On top of all that each one will mix differently with other paints consisting of other chemical compositions. It's almost impossible to learn how paints will mix if you've got to deal with scores of paints containg hundreds of different chemicals. You won't always get what you'd expect, hence, you won't be accurate and it'll take forever to conquer mixing paints to get the right value, hue and intensity you need.

Below are photos of mixing ultramarine blue and orange with a student grade hues and artist grade professional paints. The circular color chart below indicates that when you mix blue with orange you should cross a neutral gray area. Watch what happens. The top tubes are student grade cad orange hue (contains cadmium, barium, Cadmium solfoselenide) and student grade ultramarine (contains compounds of silica, alumina, suphur, soda). The bottom colors are Utrect artist grade series 3 orange (contains Cadmium Orange PO 20 (traditional cad pigments)) and series 1 ultramarine blue PB 21 (extract of Lapis Lazuli (traditional ultramarine blue) or a synthetic inorganic silicate which is chemically identical to Lapis Lazuli). Notice the student grade indeed looks orange and blue (although the intensity seems less) and the artist grade Utrect paint also looks orange and blue. When mixing together without white you can definitely see a green tint to the student grade. The artist grade looks gray. Adding white to each mixture really proves the inability to get the mixture I was trying for - which is a flat neutral gray. The student grade has turned green, the artist grade is indeed a gray and crosses the neutral gray area that you'd expect from the color chart. In fact, achieving a flat neutral gray with the student grade is practically impossible. It would need some red to offset the green, but the student grade red won't give you exactly what you'd expect either. The student grade pile will continually grow and I'd be lucky to get a gray within 20 minutes. I mixed the artist grade gray in about 20 seconds.

 Watch the Full video "Mixing Student Grade Paints

 There is a system of grading and identifying paints. Every manufacturer puts these specifications on the paint tube. It would be prudent to read these specifications before buying a tube of paint. They are:

1. Series: Generally from 1 to 5 (or A to E): 1 is fairly inexpensive, 5 is expensive.  Simply put, the series is an indication of price of a certain color. For instance, the series number on the best cadmium paints (cad red, cad yellow, cad orange, etc.) will be series 3 or 4. It's the best you can get. On the other hand, the best Ultramarine blue (containting extracts of lapis lazuli) will have a series of 1 or 2 but still of the highest quality. There are other ultramarine blues consisting of other pigments like silica, alumina, and soda that are inferior to lapis lazuli but still have a series number of 1. Some exotic paints containing manganese can be series 5. It's just a rarer, harder to produce paint. You can purchase a tube labeled cadmium red, series 1. If you look at the ingredients it may say cadmium and barium or just barium. The series 1 states that it is cheaper (because barium is cheaper than cadmium) but you have to notice the chemical composition -- that will tell you more than the series. Barium mixes badly with other paints.
2. Chemical Composition: The tube of paint should give you the chemical composition of the pigments. There should be a pigment code on the tube. Here's an example: PY 35. You can look up the paint chemical composition on the database at http://www.artiscreation.com/Color_index_names.html .
3. Hue: If you buy a tube of paint that says it's a hue it will probably contain cheaper chemical compounds (like barium or other less expensive compounds). The word Hue on a tube of paint means imitation or faux (different from hue, meaning color in normal artist terminology). Hue denotes an imitation version of another pigment, created to reduce the cost of the a true artist grade pigment. For example: Cadmium Red Hue is an imitation version of Cadmium Red. True cadmium is fairly expensive, so the hue version gives a less costly alternative but far inferior to a true traditional pigment. A hue is best used without mixing with other paints. If you mix hues with other colors you'll get strange results as show above.
   
4. Artist grade or student grade: This indication isn't on all tubes of paint. Usually a manufacturers website will break paints into categories of artist grade and student grade. For instance, Winsor Newton (thier professional grade) also makes Winton (their student grade).  Utrecht calls their professional grade "Utrecht Artists", their student grade is called "Utrecht Studio Series" (sort of misleading, they should label them "Professional" and "Student".  Also, the series and chemical composition can give you an indication of the quality. Stay away from student grade paint if you want to improve.
5. Vehicle: The vehicle is the suspension fluid for the pigment. It can be linseed oil, safflower oil, walnut oil or other suspension chemicals. The vehicle is a matter of preference and drying speed. Walnut oil is non toxic and a nice suspension vehicle but it takes longer to dry. Most oil paints use a suspension of linseed oil.
6. Light Fastness: Range from 1 to 5 (or A to E). 1 is stable and will not fade or change color when exposed to light over a period of 100’s of years. 5 is fairly un-stable and will start to fade after 20 years. Avoid paints with a lightfastness of 3 or greater. Alizarin Crimson has a lightfastness of 3. Cadmiums, ultramarine and viridian have a lightfastesess of 1.
7. Opaque vs. transparent: This isn't always on a tube of paint. Opaque paints cover well. Transparent paints are just that - semi transparent and you can see the paint or canvas underneath easier. Opaques are good to use in sunlit areas of a painting where transparents are best used in shadow areas. The most commonly used transparent colors are Alizarin, viridian and Ultramarine blue. You can mix transparent paints with opaque paints. The workhorse cadmium paints are opaque.

Know your palette with confidence. Use the best series artist grade paints. Use a limited or near limited palette. Know what to look for on a tube of paint and the chemical composition. Stay with the pigments proven over hundreds of years. If it takes you longer than 1 minute to mix and arrive at the hue, value and chromatic intensity you need for the next stroke - you don’t know your paints very well, or, you have so many different kinds of paint it's practically impossible to know the mixing characteristics. Practice makes perfect. Switching paint all the time in hopes you will find the “Perfect” paint will not help you. It takes time to learn the properties of newly introduced paint and even longer times to learn how to mix extended palettes. Buy the best traditional artist grade paints and you'll progress much faster.

Happy Painting,

Don Finkeldei