What is the cause of dark spots that sometimes appear on the paper of drawings and paintings? Reddish-brown spots are known as "foxing", caused by mold or the deterioration of the metallic impurities left in the paper from the manufacturing process. Other fine art pictures colors of spots may be one of many types of mold damage. mold spores are everywhere in the environment, and mold thrives on cellulosic materials, especially in conditions of high humidity (above 65% of relative humidity). keeping artworks out of high humidity areas like bathrooms art or exterior walls, can help reduce the development of such stains. if i have a work of art on paper that appears to not be flat, should i be concerned? paper is hygroscopic, reacting to changes in climate by expanding when it is humid and contracting when it is dry. a gentle undulation in the paper called "cockling" occurs under these conditions, especially pictures with larger works. this may impair the work aesthetically as well as cause mediums such as gouache to crack or flake as it is unable to expand and contract fine art pictures as the paper itself does.

one thing after another explores the relationship of printmaking to the proliferation of serial imagery in the contemporary period. classic serial print projects from pop art and minimalism are juxtaposed with works from 1980s and 1990s. artists included range from andy warhol, roy lichtenstein, ellsworth kelly, and brice marden to rosemarie trockel, john armleder, art yukinori yanagi, and anish kapoor. pop and after juxtaposes major works pictures of the 1960s by american and european artists, which focus on mass media and the iconography of consumer culture, with works by younger creators of the 1980s and 1990s that extend and twist the stylistic and social concerns of pop art. artists included range from andy warhol, claes fine oldenburg, and roy lichtenstein to jeff koons, david hammons, and damien hirst.

glazing can art be either glass or acrylic. only glass should be used with any friable media such as unfixed pastels, charcoals, or graphite, pictures never acrylic as it can damage the work by attracting these materials. there are many brands of acrylic glazing to choose from; one with an ultraviolet filter is recommended. the frame and the mat should be deep enough to prevent the artwork from touching the glazing. a stiff backboard behind the mat protects and supports the matted artwork. it is best to use non-acidic boards. a dust seal with paper or tape is also recommended. what damage results from using poor quality mat board? avoid mat boards containing wood pulp which causes "matburn"--a darkening of the paper under the mat or at the bevel cut of the window mat. this type of stain permanently weakens the paper fibers and is not easily removed or lightened in conservation treatment.