A Rembrandt in the room

Infra-red reflectography on the Rembrandt
Many different techniques were used to determine the authenticity of this portrait. National Trust

The painting underwent technical analysis and cleaning, Christine Sitwell, paintings conservation advisor, explains why painting identification comes down to a combination of science and experience.

Authenticating a painting

The process combines three key aspects: the curator’s knowledge of the artist’s work and style of painting; any surviving documentary evidence related to the work’s history and previous owners; and the results of analytical investigations that reveal the artist’s materials and techniques, as well as any changes that have occurred over time.
After undergoing eight months of painstaking investigative work at the world famous Hamilton Kerr Institute (HKI) in Cambridgeshire - and re-examination by the world’s leading Rembrandt expert - our Buckland Abbey self-portrait, the original ‘selfie’, has been confirmed as the first Rembrandt in our collection of 13,500 paintings.

Discover the process our painting went through;

Visual analysis

The painting is removed from its frame and conservation experts examine the front and back looking for clues such as the type of wood or changes in direction of brushstrokes. To their surprise, the wood is not beech as previously reported but an as-yet-unidentified wood that could be lime or poplar.


Thicker areas of paint may block X-rays, but they rely on the density of certain pigments, particularly lead white, to absorb the radiation and create an image on the film that may not be visible on the surface. This one shows the possible outline of a lace cuff, suggesting that the artist sketched in an arm across the chest, and then reconsidered.

Infra-red reflectography

Infra-red rays can penetrate most paint layers, except for those containing carbon-based pigments such as charcoal, graphite or black inks. It can be useful for seeing whether there is an ‘underdrawing’ beneath the paint. Here, there isn’t much underdrawing but you can see a ‘reserve’ – a lighter area around the hat, suggesting the original hat was intended to be larger but the artist changed his mind.

Raking light

By shining a light across the painting at an oblique angle, the surface characteristics, such as any raised or lifting paint, are clearly visible. In this instance, the light reveals the ‘tooling’ marks made on the reverse of the panel by the artist as he prepared the board for painting.

Paint microscopy/pigment analysis

If necessary, minute paint samples are taken from different places on a painting and examined under a light microscope. All the different layers can be seen and the pigments identified. Paint added at a later date is often separated by a thin layer of dirt or varnish. We want to see if our samples are similar to those from known Rembrandt paintings.


Once the painting has been cleaned and past restorations removed, all the fine details, brushstrokes and colours will be visible, so experts can make comparisons with known Rembrandts. The painting is not currently in its original frame, so we may reframe it in a traditional Dutch frame to make it look more authentic, before returning it to Buckland Abbey for display in March.


Players of People’s Postcode Lottery have funded £100,000 towards the Rembrandt project.
The funding provided means that we can carry out this critical technical analysis, undertake conservation to the painting where needed, and interpret the painting for all visitors through an exciting exhibition once it is returned to Buckland Abbey.