The following questions were addressed directly to the conservators during the conservation of Picasso’s Les Demoiselles d’Avignon.

I have some questions on treatments and analyses of Les Demoiselles d'Avignon. The questions are listed below.

How do you pick up the best one of hundreds of kinds of varnishes for a target oil painting in terms of colorimetry? Is there any priority of choices?

Colorimetry is not the first criterion for choosing an appropriate varnish for use in a conservation treatment. Conservators tend to use varnishes that have been formulated specifically for superior long-term aging qualities. They offer stability, good handling properties and superior optical qualities. They are soluble in a range of solvents, which offers flexibility in their application, whether via a brush or spray.

How do you manipulate the thickness of varnish? Is the thickness uniform over a painting surface? Is Manipulating thickness (thick or thin) important for a final result?

The thickness (viscosity) of the varnish is determined by the ratio of solvent to solids in the varnish mixture. This will also depend on the choice of solvent and the molecular weight of the polymer making up the varnish. One can build up a thicker coating by spraying successive layers of varnish rather than applying one thick coat with a brush. It is important to achieve the proper optical effects.

The thickness of varnish affects the appearance of a painting. (Of course, not only color but also tone). It might be a reasonable thought that a restorer try to use several techniques of varnish-thickness control with brush, spray, and whatever for a preferred result. That means varnishing is a highly artificial process, not to reproduce the original varnish made by Picasso himself.

Yes, the varnish layers can be manipulated to produce the desired effects of matte and gloss and to help disguise areas of restoration. Picasso did not varnish the painting. He objected to the appearance of varnish on modern paintings. This is one reason why we removed the discolored varnish that restorers used and decided not to revarnish Les Demoiselles d'Avignon.

Is it possible to use the different recipe or palette of oil paints from Picasso's one for filling? If so, what is a reason of the possibility?

The filling done was very minimal. The material used was a material consisting of chalk in a water-based synthetic binder. This is a reversible material unlike oil paints, which could not be safely removed at a later date.

Is it not crucial to look at the photo of an artwork taken in the previous restoration in terms of color confirmation? This question comes from the fact that a color photo sometimes does not show precious colors to us.

It is important to document the restoration stages with photography and other imaging techniques. However, we know that color photographs are susceptible to color shifts so they are unreliable documents for color matching. During the retouching stage one would only rely on a photograph to help reconstruct large areas of damage or loss. Fortunately this was not the case for Les Demoiselles d'Avignon, and the retouches could be matched to surrounding paint without having to rely on a photograph.

How many times could the painting be restored? Is it possible that one day it couldn't be restored?

The painting has been treated at least four times in less than one hundred years. Depending on the extent of the treatment the painting could be restored many times more. We don't anticipate many future restorations since the painting is monitored very closely in the museum environment. With this in mind, it is conceivable that the painting will be with us for many generations to come only requiring minimal restoration every twenty or thirty years.

I notice that on your web site you mention that although the picture is lined, the evidence indicates that the lining occurred after the paint was applied and dry, probably in 1924. I was wondering how you know that, if you think Picasso did this or someone else, and why?

We know that the lining occurred after the painting was dry since there is evidence on the surface that the heat and pressure used during the lining process caused minor deformations in the paint, such as blisters and flattened impasto. There was also residue of the glue used in the lining on top of the paint, which was removed during the recent treatment. We also know from archival evidence that Jacques Doucet sent the painting to a reliner when he acquired Les Demoiselles d'Avignon in 1924.

"Paintings that have been varnished are also cleaned, or more accurately, devarnished, when the varnish discolors over time and thus distorts the original colors of the painting. Finally, some paintings should not have been varnished at all, and a varnish can compromise the essential aesthetic." In this case, a painting that may be de-varnished, not to be re-varnished once the cleaning is finished, what steps do you take to help conserve the painting without using varnish?

The presence of the varnish on a painting, which the artist did not intend to be varnished, does not preserve the painting. Indeed it can do much to diminish the essential quality of the painting. To protect the surface of an unvarnished painting from dirt and grime there are, if necessary, a number of things we do. In some cases the paintings are framed with glass or Plexiglas to protect the surface. This not only provides a physical barrier from airborne grime but also provides a buffer against any climactic changes and (in the case of Plexiglas) protection from damaging UV light. In the case of a painting the size of Les Demoiselles d'Avignon we might decide to place a barrier in front of the work to prevent visitors from approaching too closely. Under these circumstances the only treatment necessary would be a routine dusting with a soft brush once a month or so.

How long will this restoration process take, and when will the painting be on view again?

We expect the restoration, cleaning, and retouching, along with documentation of the process, to take about six months.

How does one determine that a painting needs to be cleaned?

The cleaning of a painting may be undertaken for a number of different reasons. One frequent reason is that the surface of the painting has acquired a discoloring layer of dirt and grime, the removal of which is called a surface cleaning. Paintings that have been varnished are also cleaned, or more accurately, devarnished, when the varnish discolors over time and thus distorts the original colors of the painting. Finally, some paintings should not have been varnished at all, and a varnish can compromise the essential aesthetic of the painting. When it is clear from the historical record that a painting has been varnished that should not have been, conservators will devarnish the work—if it is safe to do so—in order to try to restore more of the original surface quality to the painting.

Why is it important that restorations be reversible?

Reversibility is essential because it allows future generations to identify and remove restoration materials from a work of art without affecting the original material of the work. Thus, if these restoration materials change or discolor they can be easily and safely replaced. Similarly, if a current restoration is, in the future, thought to be inappropriate due to additional research, it can be safely removed and redone.

I was just wondering how you match the paint when restoring. Specifically, are the types of paint used in the work available now for the restoration?

We know through technical analysis which pigments were in Picasso's palette. These pigments are still available, in more refined versions and in formulations with synthetic binding media. Light stable restoration paints are also available to today's conservator. They can be used to match Picasso's palette but have the advantage of being soluble in solutions that will not affect Picasso's original oil paint. This ensures that any restorations applied to the original are "reversible" and can be removed easily when and if necessary. The color matching is achieved with a combination of skill and experience gained from a familiarity with original artists' materials and materials available to conservators.

It is great to know that a masterpiece is getting restored to its former glory. How can you match the color (if retouching is needed) to the original that Picasso applied (since most of the early pictures taken of the piece where in black in white?).

Relying on photographs would only be necessary if there were large areas of loss requiring reconstruction during the restoration. Fortunately, this is not the case with Les Demoiselles d’Avignon. Inpainting will only be done in small, discrete areas of lost paint and the losses will be toned to match surrounding paint so that they are no longer visually distracting. In this case the color matching will be done using easily reversible restoration paints mixed to match the color and gloss of Picasso’s original oil palette.

Picasso was alive and painting recently enough to know about restoration procedures in some shape or form. Why do we think that his paintings were not meant to age? Is there a way to know that he wanted them always to appear fresh and new rather than letting them age naturally, like a fine wine?

Picasso had a philosophical approach to the condition of his works. Gertrude Stein paraphrased his thoughts: “After all, if it all ages together why not?” This restoration aims to respect that point of view—not to make the painting look fresh and new, but to make it look that it has all aged together. Thus materials that were not original are being removed and the retouching we do of lost paint will match the aged paint. Signs of aging will therefore still be evident, even after our conservation treatment is completed, without distracting from the essential power of the painting.

What characteristics of Picasso's work and style did you have to be familiar with in order to be able to intervene in his work?

An in-depth study of Picasso's painting materials preceded the treatment of Les Demoiselles d'Avignon. These materials were found to be consistent with other works from the same period, including the small study in MoMA's collection and published results of other technical studies of Picasso's work (cf. Delbourgo and Koussiaki). Information on the original materials, coupled with knowledge of the materials used by restorers/conservators in the past (e.g. wax and synthetic varnish), allowed us to arrive at an appropriate treatment that will allow Picasso's original materials to be conserved while removing restorers' later additions that have discolored over time.

What is your attitude when you face art pieces by completely different artists?

It is best to be familiar with many examples of an artist's work before a restoration is attempted. Knowing the range of materials that one may encounter helps the conservator make an informed decision about conservation treatments and materials that are both compatible with the original and easily reversible should they discolor over time.

Have you ever noticed a recurring damage or problem you have treated that is found characteristically on the work of Picasso or any other artist?

Fortunately Picasso used materials that were of high quality. His training as an academic artist meant that he knew exactly how to use art materials in a way that would ensure their longevity. Even still, his technique could sometimes be slightly at odds with his materials. He worked so quickly that sometimes under-layers of paint did not have time to thoroughly dry before he applied another layer on top. This could result in areas of drying cracks where the under-layer is visible (cf. the face of the crouching figure in Les Demoiselles d'Avignon, where a layer of cadmium yellow is visible through cracks in the uppermost paint layer). These cracks surely developed while the painting was still in Picasso's possession and maybe soon after the work was finished. Picasso was known to admire these kinds of conditions as a sign that the work had a life of its own. These drying cracks will not be altered since they are now stable and serve as evidence of Picasso's working methods.

We couldn't find a signature. Do you know about that?

Picasso did not always sign his finished works. However, paintings from this period (such as the monumental Three Women [autumn 1907–late 1908], now in the Hermitage, Saint Petersburg) were sometimes signed on the reverse of the canvas. The lining canvas applied in 1924 obscures the reverse of the original canvas of Les Demoiselles d'Avignon. It is possible that a signature exists but has remained obscured. However, our attempts to discover it through several examination techniques, including transmitted light, infrared photography, and X-rays, do not show any such signature.

Pictured at top:
Conservator Michael Duffy cleaning Les Demoiselles d'Avignon