Permanence or popularly called the “lightfastness” is the ability of the pigment in the acrylic paint for resisting probable fading when the painting is exposed to light. The pigment which is generally fading is called fugitive colours. In the cases of acrylic, almost all colours have a high ratio of permanence in comparison to oil and watercolours. Get the best permanence acrylic from Big acrylic prints for your best painting.
You need to look for a certain permanence standard in order to buy the best acrylic paint that will serve your purpose. The following are called the ASTM permanence standards.
ASTM 1: excellent permanence, ASTM 2: Very good permanence, ASTM 3: Not sufficiently permanence.
The typical manufacturer standard goes as per the following:
**** or AA: Extremely permanence colour, *** or A: Durable colour, ** or A: Moderately durable colour, * or C: Fugitive colour.
For all expect the people with experimenting, are supposed to buy and use acrylic paints with excellent or very good permanence. These ratings can be found on the tubes or jars.
The viscosity simply refers to the thickness or consistency of the acrylic paint that you are using. The heavy body acrylic has comparatively buttery and thicker consistencies like the oil paints. This consistency of heavy body acrylic retains the brush strokes and helps in blending and colour mixing. On the other hand, fluid acrylic is comparatively thinner. However, they contain similar pigment concentration like heavy body acrylic and are suitable for painting, watercolour technique, staining, and dry-brush works. Instead of these two viscosities, if you are looking for the consistency in between the heavy body acrylic and fluid acrylic, you can choose from many acrylic mediums and mix the appropriate medium in your paint for exact viscosity you require.
The viscosity depends on the type and nature of painting that you are working on and on your personal preferences. You may also prefer to use several viscosities in one painting. But this is more applicable for experienced artists. If you are a beginner, you should start with heavy body acrylic, and use acrylic mediums for thinning the paint as per your requirements.
Many things of your painting depend on the viscosity. Choosing the right viscosity and applying the appropriate viscosity is the skill of an artist. If you do not use the right medium in the right viscosity, you may not perform well in your painting.