This article opens with a distinction between David Hockney's strong and weak theses. According to the strong thesis, in the period 1430-1860, optical tools (mirrors, lenses, the camera obscura, etc.) were used in the production of paintings; according to the weak thesis, mirrors and lenses merely inspired their naturalistic look. It will be argued that while for the fifteenth and sixteenth centuries, there is little evidence in favor of the strong thesis, the case is different for the seventeenth century, for which the use of optical instruments by painters is a documented fact. In this article, an early case is examined. The extant preparatory drawings of Gaspare Vanvitelli (Gaspar van Wittel, 1652-1736) suggest that this cityscape painter relied on a camera obscura. But even here, the strong thesis must be tempered. The fact that several stages of artistic transformation separate the camera obscura projection from the finished painting undermines Hockney's analogy between optically assisted painting and 'naturalistic' photography.
Christoph Lüthy and Hans Thijssen
Alexis Smets and Christoph Lüthy
This essay examines the problems encountered in contemporary attempts to establish a typology of medieval and early modern scientific images, and to associate apparent types with certain standard meanings. Five particular issues are addressed here: (i) the unclear boundary between words and images; (ii) the problem of morphologically similar images possessing incompatible meanings; (iii) the converse problem of comparable objects or processes being expressed by extremely dissimilar visual means; (iv) the impossibility of matching modern with historical iconographical terminologies; and (v) the fact that the meaning of a given image can only be grasped in the context of the epistemological, metaphysical and social assumptions within which it is embedded. The essay ends by concluding that no scientific image can ever be understood apart from its philosophical preconditions, and that these preconditions are often explained during disputes between the protagonists of different iconographical types.