AIC-PMG Winter Meeting 2025

This paper will present an experiment to assess the light-induced fading of duplicate color slides used as exhibition copies. The project was initiated when Blocking Out the Sun was selected for a 33-week-long exhibition at the Los Angeles County Museum of Art.

Blocking Out the Sun (2004) is a slide-based artwork by artist Edgar Arceneaux (born 1972). A series of 72 35 mm color slides projected on the wall show photographs of Santa Monica beach with various colors and luminosity levels, from blue to orange shades and from dark shadows to almost white overexposed areas where the sun directly hits the film. In most images, the artist’s thumb covers the sun, a reference to a historical technique used by astronomers to measure the clarity of the atmosphere.

The significant sensitivity to light of chromogenic films has been known since the process was commercialized in the 1930s. Henry Wilhelm’s 1994 study demonstrated that light is the primary cause for color slide fading, that the most light-sensitive dye (for all six films he tested) was magenta, and that the highlights faded faster than the lowlight areas. The most stable films he tested were the Fujichrome Films, showing an “objectionable amount of change” after 5 hours and 20 minutes of cumulative exposure when projected in 30-second intervals. Wilhelm’s tests also demonstrated the reciprocity failure of reversal color films: more fading was caused by short intermittent periods than long, continuous projection times.

Using a projector causes progressive and irreversible fading; therefore, each exhibition requires the creation of duplicate sets to preserve the original master set. Since the discontinuity of the last duplicate film stock in 2010, conservators and film experts have focused on developing a suitable technology to duplicate chromogenic films. Using a LVT (Light Valve Technology) film recorder, we can now digitize film masters and print new copies on regular color film to obtain a satisfactory duplicate set for exhibition.

However, the question of how often to replace the copies still needs to be answered. Should the exhibition set be used for the entire exhibition? For multiple venues? Should the set be replaced by a new one after a certain number of weeks or months? Who decides when the film is too faded that it no longer represents the artist’s intent? These decisions depend on many variables.

For this experiment, we created color slide duplicates that were subjected to the projector light in exhibition conditions. Weekly color measurements were collected and compared after 25 weeks to document the evolution of fading and staining. The goal was to initiate a discussion with curatorial colleagues and the artist about the progressive fading of the slides and attempt to determine a “too faded” exposure threshold, after which the duplicate slides should be replaced, taking into account this particular artwork's conceptual and aesthetic aspects.