Nationalist art history
Scientific advances have made possible much more accurate investigation of the materials and techniques used to create works, especially infra-red and x-ray photographic techniques which have allowed many underdrawings of paintings to be seen again. Proper analysis of pigments used in paint is now possible, which has upset many attributions. Dendrochronology for panel paintings and radio-carbon dating for old objects in organic materials have allowed scientific methods of dating objects to confirm or upset dates derived from stylistic analysis or documentary evidence. The development of good colour photography, now held digitally and available on the internet or by other means, has transformed the study of many types of art, especially those covering objects existing in large numbers which are widely dispersed among collections, such as illuminated manuscripts and Persian miniatures, and many types of archaeological artworks.
Concurrent to those technological advances, art historians have shown increasing interest in new theoretical approaches to the nature of artworks as objects. Thing theory, actor-network theory, and object-oriented ontology have played an increasing role in art historical literature.