# What Technical Art History Can and Cannot Prove
> Dendrochronology dates a tree to within a decade and says nothing about a painting. Here is what each technique establishes, with the published figures and the failed cases.
> The Study - 2026-08-02
> Canonical HTML: https://iconotheca.com/study/what-technical-art-history-can-prove/
## Key points
- Peter Klein's Baltic oak method assumes at least nine sapwood rings and two to eight years of seasoning, which is why it yields a floor rather than a date.
- Two of the National Gallery of Victoria panels Klein examined could not be dated at all, one because it had been thinned and glued to a modern board.
- Titanium white was not available as an artists' oil colour until about 1921, which is the anachronism that exposed Beltracchi's Campendonk.
- Paint samples are taken at edges and near existing losses, which is precisely where later restoration material concentrates.
## Every technique is stronger at exclusion than at confirmation
## Dendrochronology dates the tree, and the inference does the rest
## The technique fails silently, and the failures are instructive
## Infrared reflectography, and one claim that is weaker than it sounds
## Pigment analysis is the backbone, and restoration contaminates it
## X-radiography shows structure, and reuse proves less than it seems
The proper use of technical art history is to shrink the field of possible answers and to kill the impossible ones. It sets floors under dates, exposes structures beneath surfaces, and convicts forgers on materials that did not exist. What it does not do is name a hand, and the honest practitioners say so in print: the largest technical campaign ever mounted on a single artist concluded that connoisseurship figured in every attribution it made. Anyone presenting a laboratory report as a certificate of authorship is selling a service that does not exist.
## Questions
**Which technique is most decisive?**
Pigment and binder analysis, because it can produce an outright anachronism that no argument survives. Everything else narrows the possibilities without closing them, and dendrochronology in particular yields only a terminus post quem, the earliest date at which a panel could have been painted.
**Can technical analysis identify which artist painted a picture?**
Rarely on its own. It establishes date range, structure, materials and working method, and assigning those to a named individual remains an argument built with connoisseurship. The Bosch project's own conclusion after years of instrumentation was that connoisseurship figured in every attribution it made.
**Why did a dendrochronological report come back with no result?**
Usually one of two reasons. The panel was thinned or cradled by an earlier restorer, destroying the ring sequence, or the sequence matched no existing regional master chronology. Klein reports both outcomes among the panels he examined at the National Gallery of Victoria.
**Does a picture without technical analysis have a problem?**
Not necessarily. Analysis is expensive, sometimes invasive, and is normally commissioned when there is a question worth the cost. Conservation guidance also recognises that sampling is occasionally inappropriate for a given object on ethical grounds.
## Sources
- [1] Peter Klein, 'A note on dendrochronological analyses of panel paintings at the National Gallery of Victoria', Art Journal 40, National Gallery of Victoria.
- [2] Matthijs Ilsink, 'Jheronimus Bosch and Connoisseurship: Remarks Prompted by the Bosch Research and Conservation Project', CODART, December 2015.
- [3] CODART, 'According to Bosch Research and Conservation Project two paintings likely to be imitations and new drawing attributed', 2 November 2015.
- [4] Jane Kallir, 'Art authentication is not an exact science', The Art Newspaper, 23 November 2018.
- [5] Museo Nacional Thyssen-Bornemisza, 'Infrared Reflectography', conservation section.
- [6] ColourLex, 'IR Reflectography', on the wavelength ranges of films and modern cameras.
- [7] WebExhibits, 'Pigments through the Ages: Titanium Dioxide Whites'. Tertiary reference source; should be replaced with Marilyn Laver, 'Titanium Dioxide Whites', Artists' Pigments vol. 3, Oxford University Press, 1997.
- [8] ColourLex, 'Prussian Blue', on its 1704 discovery as the oldest modern synthetic pigment.
- [9] ColourLex, 'Zinc White'.
- [10] University of Delaware, Art Conservation Resources, 'Examination Methods and Scientific Terms', on cross-sections and sampling locations.
- [11] ColourLex, 'X-Ray Radiography', including Bellini's Feast of the Gods.
- [12] ColourLex, 'Neutron Activation Autoradiography', on Rembrandt's An Old Man in Military Costume.
- [13] The Phillips Collection, collection entry for Pablo Picasso, The Blue Room.