Restoring Former Glory with Cotton Buds and a Microscope – The Princely Collections of Liechtenstein

Schué, Anja; Klebel, Ruth

December 14, 2009

Restoring Former Glory with Cotton Buds and a Microscope – The Princely Collections of Liechtenstein

On her way to work, Ruth Klebel is often approached by tourists asking for the times of guided tours. She always gives the same answer before disappearing behind the wide automatic gate: "I’m afraid there aren’t any, this is private property." As a restorer of the collections of the Prince of Liechtenstein, Klebel is one of the very few people who regularly come and go at Vaduz Castle without actually living here. Standing in solitary splendour on a rock terrace high above the capital of the principality of Liechtenstein, the castle is the home of one of Europe’s oldest aristocratic families.

A bearer of this name, Hugo von Liechtenstein was first mentioned around 1136. The beginnings of the Princely Collections date back to the time of the family’s rise to princedom in the 16^th and 17^th centuries – a time of intensive patronage of the arts by the European aristocracy.

At home in Vaduz – exhibited in Vienna

Since the restoration of Vaduz Castle in 1938 and the move of the Princely Family to Vaduz, this is the home of the collections, too. However, only a few of the art treasures are open to the public, and most of these are housed in the LIECHTENSTEIN MUSEUM in Vienna – the city that has played a key role in the life of the family for many generations. Temporary exhibitions in the LIECHTENSTEIN MUSEUM in Vaduz give further insights into the diversity of the collection.

Today, the Princely Collections rank among the most important private art collections worldwide, and the Princely Family still takes an active part in adding to them. They mostly comprise works from the period between the 15^th and 19^th centuries, with a focus on early 17^th century Baroque paintings. Besides bronze sculptures and decorative arts, they also include a notable Biedermeier collection, which is to be exhibited in Vienna’s Stadtpalais in a few years’ time. At present, the building is still undergoing renovation. Klebel, who also has her own studio in Bregenz as well as working as a member of the restoration team for the Princely Collections in Vaduz, mainly looks after the paintings. Her job involves conservation, restoration, supervising storage conditions, and drafting loan and transport evaluations.

Ms Klebel, what are you working on at the moment?

My present task is a work of the Dutch painter Willem van Honthorst from the first half of the 17^th century. It shows the almost life-size portrait of a young man with a plumed hat. The canvas of this painting has to be repaired as the edges have been damaged by excessive tension. The surface of the painting will also be treated, areas of earlier repainting will be removed and the degraded varnish will be reduced with appropriate solvents.

The surface of the portrait is unusually rough. Looking through the stereomicroscope, I noticed that the roughness is caused by grains/impurities in the varnish. This layer was definitely applied at a later date than the execution of the painting. Restoring old paintings is often not only a matter of repairing damage to the original substance. Most paintings have already been reworked or restored in the past, and not all efforts have had a positive influence on the original substance.

Art restoration did not become a profession in its own right until the 19^th century. Before this, restoration work was frequently done by painters, who overpainted missing areas or even whole sections of the picture. If possible and advisible, we remove these layers, as our aim is to restore the original intention of the artist in relation to the age of the artwork.

Fig. 1: Willem van Honthorst (1594–1666): "Portrait of a Young Man Holding a Plumed Hat in his Right Hand". The almost life-size portrait dating from the first half of the 17^th century requires extensive restoration. © Sammlungen des Fürsten von und zu Liechtenstein, Vaduz – Wien.

What do you use the microscope for?

For one thing, the microscope is used to examine works of art. I take an exact look at the paint layers, as well as the support which can be from canvas, wood, metal, glass etc. …, to localise and identify the source of specific types of damage. The state of preservation of the painting is also documented with various types of photographs using different light sources. For sophisticated conservation and restoration work, such as stabilising loose paint layers or removing layers of non-original material, the microscope is indispensable. I use a stereomicroscope with floor stand, which offers the flexibility and reach I need for working on large objects. Both for working on the painting itself and for the photographic documentation, it’s essential that the microscope/stand combination is highly stable and as vibration-free as possible.

Fig. 2: The microscope examination shows the rough granular surface of this Dutch painting which is a result of a later application of varnish with poorly dissolved components. © Sammlungen des Fürsten von und zu Liechtenstein, Vaduz – Wien

How do you use the microscope for the repair of the canvas?

The microscope is in vital for repairing tears and holes in the canvas, too. The torn ends of the threads are rejoined with one single spot of adhesive. The pattern of the weave is imitated and it is ensured that the tension of the glued threads is the same as that of the intact fabric, as otherwise bulges or indentations appear in the repaired area. This procedure can be tremendously time-consuming.

An example of canvas repair is a still life of flowers by the Dutch painter Rachel Ruysch dating from about 1700. The microscope was crucial for this restoration process. The painting was relined, that means a second canvas had been adhered to the reverse of the original canvas support to help stabilise it. It was decided to remove this second canvas, which subsequently left most of the old adhesive attached to the reverse of the original support. This residue was removed under the stereomicroscope with a highly tuned air abrasive device. The original canvas also had many losses due to insect infestation which penetrated to the paint layer. The missing threads in these areas were replaced by new ones which were glued to the ends of the original threads.

Fig. 3: Rachel Ruysch (1664–1750), "Flowers in a Vase", ca. 1700. Here, the severely damaged canvas was restored, the degraded varnish reduced, non-original layers removed and damaged paint layers retouched. © Sammlungen des Fürsten von und zu Liechtenstein, Vaduz – Wien.

Fig. 4: To repair tears in the original canvas, threads are individually inserted and adhered to the intact fabric under the microscope. © Sammlungen des Fürsten von und zu Liechtenstein, Vaduz – Wien.

How important are illumination and ergonomics?

The illumination plays a very important role. It has to be variable and precisely adjustable, and the arm must not get in the way. We often have to move the light quite close up to the surface of the painting. To resolve extremely fine changes to the surface and raised structures, we need raking light – having the surface illuminated at an extreme angle from the side, usually from the left. Flexible illumination is critical for photography, as well. I spend a lot of time with the microscope – some days with five- to six-hour sessions. The work requires absolute concentration, so ergonomics is a serious issue for me. I make sure I sit in a comfortable position and I find features such as tube with an adjustable viewing angle of 0–180 ° very helpful in making spells at the microscope less tiring.

Fig. 5: After uncovering the original paint layer of the still life, details of a campanula become visible under the microscope. © Sammlungen des Fürsten von und zu Liechtenstein, Vaduz – Wien.