This black-and-white picture was taken during an exhibition in 1980 at Salon O, a former exhibition centre in Leiden, the Netherlands. [figure 1] It is a picture of the work 25 Caramboles and Variations: A Birthday Present for a 25 Year Old (1979) by Miguel-Ángel Cárdenas. We see three rather big monitors on a wooden construction suggesting a billiard table. The films on the monitors show billiard balls rolling from one screen to the next. Originally, in 1979, the images of the billiard balls were shot on blackand- white film and these images were shown on monitors placed on a real billiard table in a pub in Amsterdam. The work was, as the title indicates, a birthday present for a friend: a live event during an opening of an exhibition in a gallery near that same pub. A year later, the artist was able to shoot the images in colour film, and so he did. By that time the work had been acquired by the Stedelijk Museum in Amsterdam: three U-matic tapes and a very brief description of the work. Over the years, it was presented on several occasions and in diverse manners. Each time, the work looked very different. On one occasion, for example, the monitors were placed in the corners of an exhibition space. In this particular display, the surroundings of 25 Caramboles became part of the work; the spectator entered, as it were, the game of the billiard balls, rolling from one corner to the other.

In 2003, nearly twenty-five years after its first presentation in the pub, the work was on loan and reinstalled at the exhibition 30 Years of Dutch Video Art at the Netherlands Media Art Institute/Montevideo Time Based Arts (NIMk) in Amsterdam. As a researcher at the Cultural Heritage Agency of the Netherlands, I was, at the time, asked to join the NIMk team in their research for this exhibition. Working closely with the head of collection, the head of conservation, the curator of the exhibition, the artists involved and the technicians, my task was to trace the histories of a number of these installations and to make an analysis of their conservation problems.