Exhibiting this work is a challenge: it is a very large canvas that is not mounted on a stretcher, with a very fragile ‘paint layer’: Paintstick is an oil pastel that does not harden but remains soft. This makes the material very sensitive to damage, such as fingerprints and scratches.
Fragile and large
Treatment was necessary to install the work. The edges of the canvas had been weakened by the previous attachments to the wall and the Paintstick layer had acquired an irregular appearance due to degradation of the material: deposited fatty acids from the oil pastel had caused a blotchy white haze on the black surface.
But how do you treat a canvas that is so difficult to handle and has such a fragile top layer?
Plan of action
With Astrid van den Berg, freelance conservator, and our exhibitions department, we drew up a plan of action to treat and handle the work in a safe manner.
The canvas was first placed on a sturdy plastic foil so that it could be lifted and moved. It was then placed on a table made especially for this purpose, to ensure it remained flat while all the edges received treatment.. It was not possible to treat the white haze on the entire surface in this position , as the centre of the canvas was inaccessible from the edges.
The finishing touch in the exhibition space
To be able to reach all parts of the canvas, a 5.5-metre-long, semi-circular trestle was constructed. The canvas was carefully hung over this in order to treat the blotchy appearance of the surface. A narrow strip on top of the trestle, where the conservator could not easily reach, was treated in the exhibition space after the installation of the work. There, it was possible to take enough distance from the work to assess whether the treatment of the white haze had produced the desired result: a nice andeven black surface. The large size of this canvas also had an advantage: the required social distance of 1.5 metres as part of the Coronavirus measures could be maintained during both the handling and treatment.
Madeleine Bisschoff, paintings conservator