SUSIE'S REPLY: These are multi-million dollar questions! I'll try to break this down and make it as simple as I can. A quick review of basic color theory reminds us there are three (3) primary colors: RED - YELLOW - BLUE.
We can not make these hues by mixing. We can create variations of each hue by adding one or both of the other colors but we can not mix up a true red, yellow or blue.
Secondary colors or hues (green, orange, and purple) are created by mixing two primaries. Red+yellow=orange; red+blue=purple; blue+yellow=green
Any time the other primary is added chances are the color will be muddy.Example: blue+yellow=green + a tiny bit of red= olive green; not a clean clear true green.
When we use a paint that has the third primary color already premixed into the tube the result is a neutralized or grayed or muddy looking color.
So, in answer to your question about what paint colors can be mixed together without making mud we do need to consider what's already in the tube of paint. Anytime you have a combination of all three primaries you will have a duller more neutralized color. The more equal the amounts of the three colors the muddier or grayer the color will be.
Think about it this way: if a color looks greenish, you know it has blue and yellow in it. If you mix that color with any color that has some red in it the possibility for mixing mud is greater. The more equal the ratio of red + yellow + blue the more neutral the resulting color will be.
Many times we create duller looking colors by over mixing them in our palettes before we apply them to our watercolor paper. If we allow these same colors to "mingle" on our paper and mix together naturally they usually do so in a visually pleasing way.
As for premixed tube color formulas: There are probably as many "formulas" for mixing visually pleasing neutrals as their are watercolorists. For a dark gray or black one very popular combination is Ultramarine Blue and Burnt Sienna. Another formula for black is Alizarin Crimson and Hookers Green.
Here are some tips:
- Testing the colors on your own palette to see what color combinations you can make will be helpful. Make a color chart. Avoid mixing more than three colors, better yet try not to mix more than two premixed tube colors.
- Read the labels on your paint tubes. If they contain two or more pigments know that they are good candidates for mud makers when mixed with additional colors using multi-pigments.
- Another thing to consider is that each brand of paint has different ingredients even though it may have the same color name. So one brand of cobalt blue may mix up differently than another brand of cobalt blue.
My personal recommendation for all new painters ( or anyone who is confused about mixing colors) is to use a limited palette of basic compatible core colors. The brand of paint isn't as important as the choice of your basic colors. Stick to using this limited palette for a period of time to allow you to get acquainted with color mixing and learn all you can about what these core colors will and will not do for you. If you are a prolific painter six months may be enough time for you to work with a limited palette. If you don't have time or don't paint very often you may need as much as a year of working with a limited palette to get the hang of color mixing.
For more information look for my article published by Daniel Smith Some Thoughts on Color and using a Split Primary Palette.
Hang in there! The more you practice the better you will get!
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