Restoring Kneller: Care & Conservation of Baroque Portraits

In the late 17th century, there was an artistic boom in England – thanks in part to the protestant, Netherlandish influence that dominated the court following the Civil War. Many of the leading portraitists flourished due to their craft becoming accessible to all manner of aristocrats and those in upper class families – hoping to climb socially and economically. 

In this era, portraiture was not only to establish a likeness of the sitter – it was to firmly display their standing in society. For women, it was to share their good nature and eligibility with those they wished to suit – or to simply record their beauty and influence in court. In these circles, two names dominate the patronage, Peter Lely and Godfrey Kneller. 

Painters of the Grand Manner

Peter Lely had led a tumultuous career as court artist to Charles I, Oliver Cromwell and Charles II by the time Godfrey Kneller arrived in England. Lely’s work in the field of portraiture would set a standard for the next hundred years, forming the era’s understanding of idyllic beauty through the use of classical undertones and luxurious drapery. To this day, Lely’s Windsor Beauties are some of the most well known pieces of art from England in this period.

Above: detail from a portrait of Mary Capel and her sister by Peter Lely, 17th century

Lely travelled to England two years after the death of influential court painter Anthony van Dyck. Kneller travelled Europe before settling in London in 1676 – just 4 years before the death of Lely. This string of artists from the low countries had a profound impact on the styles that were used and the aesthetic quality that was most admired by the aristocracy.

Kneller’s dominance of portraiture in the late 17th and early 18th century would become known as the ‘Grand Manner’ – an accumulation of artistic grandeur built up by the likes of Van Dyck and Lely into the high baroque period. The use of classical symbolism allowed both the sitter and the artist to portray themselves as higher than their mortal position. For the sitter, it aligned them with the virtue of antique deities, for the artist, it allowed them to practice a superior form of art.

Above: a variety of unfinished artworks by Kneller, including a self portrait (centre) 

Signs of Historic Damage

Due to their age, old master portraits by the likes of Kneller can face a variety of deterioration due to their environment. The physical history of an antique painting can be complex. 

Over hundreds of years, they may have been exposed to airborne contaminants such as smoke and nicotine, or had fluctuations in humidity leading to cracks and moisture damage. In extreme cases, they may have faced severe mould growth, as well as direct issues from floods and fires.

Above: a portrait may present with a darkened surface from historic contaminants, smoke exposure or aged varnish

The following visual disturbances may indicate prior exposure or structural deterioration:

• White or cloudy surface: moisture damage or mould
• Darkened surface: smoke staining or aged varnish
• Yellow surface: nicotine staining or aged varnish
• Cracked areas: if they are stable this may be a natural drying pattern, if they are wide and/or unstable this may be an issue with their past environment or impact damage
• Uneven paint layer: old over-painting and historic repairs
• Slack or lifting canvas: in need of restretching or a new lining
• Holes in the stretcher bars / frame: historic or ongoing woodworm infestation

These issues can be resolved with sensitive intervention by conservators. Due to the age and value of these artworks, it is never recommended to try and intervene at home as a ‘quick fix’ may result in further damage or deterioration.

Caring for Antique Portraits

Ideal atmospheric conditions for antique paintings on canvas are 18 to 20 degrees celsius and between 45-55% relative humidity. To prevent drastic changes in their environment, keep all artworks out of direct sunlight and avoid hanging them near bright artificial lighting. If a painting is hanging against an exterior wall or within a room that has previously been subject to mould issues, you may want to consider moving it to a more stable setting and away from walls that may be prone to moisture in winter months. 

Frames and their hanging apparatus should be as stable as possible to avoid accident falls. Do not rely on old hanging materials if you are uncertain of their strength. If a frame is loose, it may abrade the edges of the painting or fall apart over time – leaving the canvas vulnerable. 

Options for Conservation & Restoration

It is certainly possible that your baroque portrait has survived in good condition. When this is the case, our conservators will advise against any unnecessary intervention. The painting may benefit from a professional surface clean and re-tensioning as part of its ongoing maintenance. 

For damaged paintings or those that have discoloured and began to deteriorate, a wide variety of treatments are available – all aimed at achieving the most suitable outcome for the individual artwork and its unique requirements. This is determined after a series of assessment processes and testing, looking at the painting under different forms of lighting to understand its condition and sensitivities. The assigned conservator comes up with a treatment plan that will address the issues without harming the historic and artistic value of the piece.

Above: a conservator retouching the lost pigment on a heavily cracked painting 

Typical treatments proposals may include:

• Surface cleaning using small, hand-rolled cotton swabs
• Varnish removal with a carefully tested solution
• Consolidation of cracked, lifting or flaking paint
• Stabilisation of the canvas lining 
• Re-tensioning of the original stretcher bars or re-installation
• Stabilisation, repair and cleaning of the frame
• Canvas tear repairs, conducted thread-by-thread under a microscope

Depending on the level of issues that face a painting, our team may be able to offer a sliding scale of treatment options, from a light clean through to a full campaign. 

We are happy to offer initial plans and estimated costs based on photographs and dimensions, so please get in touch below to arrange contact with our specialists. 

Speak To Our Team

Please contact us to discuss your baroque portraits restoration project, no matter how complex it may seem. Our team of experts is happy to help.

As part of our service we offer a nationwide collection and delivery service as well as information on worldwide shipping to our studio. E-mail us via [email protected] or call 0207 112 7576 for more information.