When you start to research artist supplies, one of the conversations you soon run into is that of the longevity of the piece of art you’re creating. One of the things that determines the longevity is the lightfastness of the materials that you’re using to create art.
What is lightfastness?
It’s a measure of how resistant a pigment is to change when it is exposed to light.
All paint materials – be they acrylics, oils, or watercolours, or pastels, colorpencils or gelatos, are made up of pigments that are mixed with different binding agents. Each of these pigments reacts to light exposure differently. Some break down on exposure to light – which means that the colors may fade or change over a period of time – others are more robust.
But how is an artist to know how lightfast their materials are? This is where lightfastness ratings come into play.
Most artist grade paints display ASTM (American Society for Testing and Materials standard) ratings, which is a worldwide standard for permanence that was established in 1984.
The lightfastness ratings are:
ASTM I — Excellent Lightfastness
ASTM II — Very Good Lightfastness
ASTM III — Not Sufficiently Lightfast to be used in artists’ paints
Camel’s artist acrylics use a grading system to display lightfastness – paints marked A are absolutely permanent, B are permanent and C are fairly permanent. Craft paints rarely have lightfastness information mentioned. In fact, even some artist grade paints have low lightfastness ratings.It’s also quite unlikely that craft paints and student grade art materials will have lightfastness information mentioned. In fact, even some artist grade paints have low lightfastness ratings.
So, what’s an artist to do?
Protecting artwork that is to be displayed
If you plan to display your artwork – be it on paper, canvas, or any other medium, and have no idea about the lightfastness of the supplies you’ve used, make sure to frame it using UV protective glass. This will protect your colors and keep them nice and vibrant.
Lightfastness for art journals
As an art journal artist, I don’t worry about lightfastness at all. All my art is protected between the covers of a book, which are stored safely on a shelf or cupboard. Plus, it’s easy to photograph or scan art journal spreads and get them printed on paper or canvas, which can then be framed and displayed.
Of course, there are a lot of other factors that determine how well your art will age. But those are posts for another time!
Over to you: are you concerned about preserving your artwork for the ages? Or would you rather have fun with paints without bothering about things like lightfastness and longevity?