Examining Mediums

Working with any painting material will lead you to the use of a variety of medium preparations.  Every type of paint has a full complement of mediums to assist the artist in achieving everything from general painting to special effects.  Most all mediums have one thing in common, regardless of the material they are designed to work with:  They all seem to offer a smoothing, softening or viscosity-adjusting element to the ground component.

Oil paints have the largest number of supporting and altering mediums available.  For centuries linseed oil, for instance, was used not only in the composition but also the thinning and softening of oil paints.  Today’s linseed oil is super refined and used by many oil painters as a standard medium.  Thinners such as turpentine and solvents like white spirits can be used for everything from oil washes to cleaning brushes and palettes.  New age products such as drying gel mediums, matte oils and impasto oil create new directions which artists can explore.

Linseed oil is a high viscosity, alkali refined oil that helps hide brushstrokes and increase brightness and glossiness of oil paint colors.  One downside to linseed oil is its tendency to yellow over time.  Cost is a plus, as linseed oil is not especially expensive and is available at all art material suppliers.  As long as it is not contaminated with organic material, the oil will remain usable for many months.

Thinners such as turpentine have been around for centuries, too.  Today, however, they have added refinement including odorless solvent suitable for indoor use or for people who are sensitive to the odor of normal solvents.  An excellent thinner, turpentine also is the perfect brush cleaner for oil painters. 

Exotic oils such as poppy, walnut and safflower oils offer increased brightness with less yellowing than linseed oil.  Poppy, for instance, is extremely pure and will not yellow and is very well suited for whites and other light colors.  Walnut oil is more like linseed, but with good drying properties and less yellowing.  Safflower is used to soften and make more fluid oil paints.  It is very pure, dries quickly and does not yellow.

Acrylic mediums are not as varied, but perform very well with acrylic paints.  Many brands are made in both liquid and gel forms, offering a much more varied application.  Surface qualities include matte and gloss, and a few manufacturers offer semi-gloss.  Liquid mediums are more fluid than most acrylic paints, so they can be used to easily soften a color without diluting the strength of that color.  Gels are used in the same way, but do not soften the paint.  Rather, they add bulk without changing the strength of a given paint.  This is especially helpful in impasto work or other thick applications such as palette knife or strong brush work.

It is recommended that in order to maintain the integrity of an acrylic paint color, the artist should not use water to dilute the color but should instead use medium.  Most acrylic painters use water to some degree in their work, besides the obvious use as a brush cleaning agent.  But use of mediums is highly recommended when possible.

Super thick acrylic mediums such as dense gel medium are colorless glazing mediums with high viscosity.  They add improved flow to acrylic paints, giving them a smooth texture.  Note:  Thick medium is also a great adhesive for mixed media artists who incorporate found items on their canvases.  The gel adheres and coats the items for a permanent and lustrous finish. 

Watercolorists have some mediums from which to choose.  In actuality, liquid latex mask is a type of medium; it dries to a flexible water-resistant film that is easy to remove.  One of the easiest ways to maintain stark whites in a work is to use liquid mask.

Ox gall medium is used by watercolorists, a few drops at a time, to increase the fluidity of watercolors.  The use of ox gall will improve the flow and adhesion of watercolor.

Watercolor medium increases the transparency and brightness of watercolor.  It improves adhesion and spreads the brush stroke--very useful for layering and for overpainting tonal areas.  Although milky when wet, it dries clear.

Mediums can be used with other materials than those they were manufactured to assist.  For instance, pastels and acrylic mediums can be combined to create a most unique type of permanent “frozen chalk” look.  By working pastel into an area of lightly applied acrylic matte medium, you can freeze the strokes and adhere them at the same time.  Some experimentation is needed to establish the correct ratio of medium to pastel, but that is half the fun. 

Mediums are not only great in assisting artists with the fluidity of their paints, but also as a helpful life-extending component.  Mediums and finish coatings can serve to block UV deterioration and lengthen the life of the paint and substrate.  They help the artist to create creamy consistency or thicken the viscosity, depending on need--versatility and utility both in one product.

Explore the possibilities of some of the newer, refined mediums and see what they can offer you.