New Insights into the Cleaning of Paintings

10 • smithsonian contributions to museum conservation
occurred many times since the nineteenth century. Examples include
works by Hans von Marée, Arnold Böcklin, and Joshua
Reynolds. Hans von Marée painted an almost uncountable number
(up to 70) of oil and tempera layers, one on top of the other.
Böcklin had phases with wax techniques, did experiments with
antique encaustics, painted with tempera, and used varnish. He
was unbelievably innovative, to the detriment of conservators.
More importantly, a carefully prepared condition report
must be the basis for every decision made during the subsequent
restoration. It must contain all information about the work of
art, including a precise listing of all visible phenomena without
interpretation or judgment. Knowledge about topographic features,
the various paintings traditions, and individual painting
techniques and experiments is necessary. However, sources of information
are often scarce. This is also one of the reasons why the
Munich Pinakothek museums prefer in many cases to perform a
careful reduction in the varnish rather than a total removal.
Cleaning interventions still run the risk of damaging the
original paint layer and are the cause of the greatest changes in
aesthetic appearance of paintings. Obviously, cleaning is always
based on subjective criteria. However, the goal should still be
to proceed on a historical basis and from technical as well as
aesthetic viewpoints. The motto should be “first observe, then
act.” In order to fulfill the task of preserving the original, practical
and technical skills, broad knowledge, and ethical principles
serve equally as fundamental criteria for all restoration decisions.
Only these criteria and their use can be the leading principle for a
relatively objective work, free of the fashion of the time.
Art historians, scientists, and conservators share one thing
in common: the painting under discussion. A discussion that focuses
on an analysis of what a work of art is saying, what the
artist intended, and what the artist’s working and living conditions
were as related to the society at the time should fascinate
and enrich all participants.
BRIEF CONCLUSIONS
Less is more. On the basis of the experience at the Munich
Pinakothek museums this is applicable to all areas of restoration
and conservation. Conservators often have to deal with interventions
that their predecessors performed in previous decades to
the best of their knowledge and with the best methods at the
time. These interventions have, in some cases, compromised the
integrity of the paintings. Even if the gentler methods of the
twenty- first century are used, conservators should be aware that
they most likely will not be able to assess whether their work
has been sufficiently gentle. However, there are no hard and fast
rules. The best one can do is to be aware of the whole intervention,
ask meaningful questions, and pay attention to associations
and correlations. Although this should prove reassuring, it may
also be disquieting.
Acknowledgments
I thank, first of all, my friend W. “Bill” Wei of the Netherlands
Institute for Cultural Heritage, Amsterdam, for the
translation, editing, and revising of this text. I also gratefully
acknowledge Hans Otto Wiebus for revising the manuscript, as
well as my colleagues and the photographers of the Doerner Institute
for their support. Last but not least, thanks are owed to
Laura Fuster- López, Teresa Domenech, and Ignasi Girones- Sarró
of the Polytechnic University of Valencia for the invitation to the
excellent Cleaning 2010 International Conference.
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