Physically, the purpose of matting is to protect the artwork. Changes of temperature and humidity may cause moisture to condense on the inside of the glass and damage the artwork. By creating a small air pocket between
the picture and the glass, the matting prevents this condensation from settling on the paper and eventually growing mold.
Esthetically, its function is to support the picture by isolating it from its surroundings and to provide a neutral space for the eye between the art and frame.
By selecting matting for a piece of artwork the designer creates an overall visual continuity between the artwork and the framing materials so that the artwork
There is a misconception that wide mats will overpower a picture and bring more attention to the frame than the art. But matting that is too narrow will make
the frame look out of proportion and will draw undue attention to the frame.
There are no steadfast rules for the proportions of matting, width of the margin or placement of the window. There are, however, a few rules dictated by common
sense, general practice and basic rules of design:
- The width of a mat may vary according to the size of the picture and the effect you want to achieve. It should however, be wide enough to serve its esthetic
- There should be a marked difference between the width of the mat and frame. It stands to reason that 2 inches of matting between a picture and a 1-1/2 or
2-inch wide frame will look cramped and ungraceful. Inside a 3-inch frame, it does not fulfill its function and becomes a liner.
- Because of an optical illusion that tends to make the bottom of a mat appear narrower if the window is centered, a wider bottom margin is sometimes
used- referred to as a drop bottom.
While a single mat is all that is needed to provide the protective and esthetic properties; double and triple mats are used to accent certain colors or
hues and brings depth to the image.
Depth and drama can also be achieved by layering fabric and texture mats.