Infrared photography will often clarify inscriptions that are difficult to read because the wood or label has oxidised to a dark colour, so there is no longer enough contrast between the pencil or ink, and the wood or paper.
Infrared photography can increase the contrast and make an inscription legible.
It does not always work but when it does the results can be quite dramatic. He might be able to gain a bit more information this way.
Steven Erisoty
Paintings Conservation
Philadelphia, PA
