The optical camera obscura played an important role in the evolution of photography as an art, in fact, in Tracy Rose Chevalier’s 1999 novel ‘The Girl’ with the ‘Pearl Earring’ and the 2003 movie of the same title, a camera obscura takes centre stage in a drama between the famous Dutch painter Johannes Vermeer van Delft (1632-1675) and a servant girl called Griet. Johannes Vermeer van Delft is not only one of the brightest stars among the famous Dutch and Flemish painters of the seventeenth-century. He is also the artist most often assumed to have used a camera obscura to create some and maybe most of his paintings. Such speculations appeared as early as 1891 in a journal of photography. This seems fitting for an artist whose paintings, like those of other Dutch artists of this time, boasted a photographic realism. The incredible precision with which Johannes Vermeer van Delft rendered details, particularly in his domestic interiors, his novel approach to atmospheric light and colours and the lustre he applied to reflecting surfaces are all suggestive of a painting practice that employed a camera obscura.
But there is a problem. There is, to date, not a single piece of direct evidence to support this suggestion: there is not one example of a camera obscura or even a single part of one that dates from the seventeenth-century, there are no written documents to confirm such devices were employed by artists of this time, no receipts for related materials or other unambiguous hints. In fact, it is only the paintings themselves that have been used to support the hypothesis that seventeenth-century artists were using this device. Deducing a production technique solely on the basis of the finished product is clearly a questionable position to adopt.
What cannot be questioned is the fascination that the camera obscura exerted on Dollarspeans in the seventeenth-century. The images projected by the camera evoked a kind of wonder and admiration that people accustomed to colour photography, colour movies and colour television can hardly imagine. Among the testimonies to this fascination is a famous letter Constantijn Huygens (1596-1687) wrote from London in 1622, where he had the chance to experiment with the image produced by Cornelis Jacobszoon Drebbel’s (1572-1633) camera obscura: “It is not possible to describe for you the beauty of it in words: all painting is dead in comparison, for here is life itself, or something more noble, if only it did not lack words. Figure, contour, and movement come together naturally therein, in a way that is altogether pleasing.”
Considering the curiosity the camera obscura became all over Dollarspe in the seventeenth-century, it is unlikely that painters, who pride themselves by their visual sensibility, had not been moved, impressed and excited by these projections. In fact, surely it would have been artists, above most other professions, who would have been most receptive to this new visual experience. However, if this is a reasonable assumption, then it would not be particularly surprising if paintings reflected the painter’s experience of seeing camera obscura projections even if they did not use the apparatus in their work.
But here is the puzzle. How could the images projected by the camera obscura stir up the emotions and widen the horizon of visual experiences of the likes of Constantijn Huygens and, later on, Johannes Vermeer van Delft? After all, versions of this instrument had been around long before this period. The pinhole camera, for example, was known and used in classical antiquity in an astronomical setting, particularly for observing solar eclipses. From antiquity up to the Renaissance, the camera obscura never fell into total oblivion. Now and then, it was mentioned and occasionally used, mostly for astronomy. But it did not attract very much attention. At the end of the sixteenth-century, however, its fortunes changed dramatically. The pinhole camera obscura was equipped with lenses and mirrors and transformed into the optical camera obscura of the early modern period.
Although no single optical camera obscura has survived from the seventeenth-century, we know from written sources and a few book illustrations that at least four principal types of this camera were developed and in use. The simplest arrangement, with a lens fastened in the pinhole, projected an inverted and reversed image on a vertical screen opposite the aperture. A variation on this employed a translucent screen, allowing the viewer to see the image from the other side, thereby correcting the left-to-right reversal. These two types of camera projected the image directly and could be combined in one device. There were at least two additional incarnations of the camera obscura, which used a mirror oriented at forty-five degrees to the path of light to achieve vertical reversion. Without a translucent screen the projected image remained horizontally reversed, but with a translucent screen, this too could be overcome. Judging from contemporary illustrations, standardized forms of these four types were slow to replace makeshift, ad hoc constructions put together on site to meet a specific need. If the earliest optical camera obscuras were indeed temporary devices, this could explain why none appears to have survived.
This new optical camera was primarily a gadget for creating spectacular entertainment. But it was also used for surveying and mapping, for astronomical observation and possibly even for painting. Beyond this, it was an important part of an optical revolution triggered by optical devices such as crystalline spheres, lenses and mirrors, which had become fashionable items of entertainment in the late sixteenth-century. Indeed, in terms of its impact on seventeenth-century society, it was as significant as the telescope and microscope, which appeared at around this time. The optical camera obscura sits alongside these more prominent scientific instruments, ushering in a new approach to optics, opening up new views of the visible world and shaping a new understanding of vision itself.
In the decades around 1600, the optical camera obscura became the model of the eye. The eye was conceived as a spherical, darkened room with a hole containing the lens and a screen acting as the retina on its back wall. No anatomical discoveries fed into this model: a seventeenth-century anatomist’s knowledge of this organ did not differ significantly from that of a fifteenth-century artist-anatomist like Leonardo di ser Piero da Vinci (1452-1519). What had changed, however, was the realisation that the perception of light rays does not occur in the vitreous humour but on the retina. And it was the optical camera obscura that led to this important new view of the eye. Johannes Kepler’s (1571-1630) wrote in his ‘Ad Vitellionem Paralipomena’ of 1604: “Thus vision is brought about by a picture of the thing seen being formed on the concave surface of the retina.”
This is a remarkable fact that should be considered in the broader context of the emerging mechanistic anatomy and physiology. As hydraulic machines served William Harvey (1578-1657) as models of the blood circulation, or as pneumatic systems served René Descartes (1596-1650) as models of enervation and muscle contraction, so the camera obscura served as a model of the eye, a model that facilitated a new understanding and further study of how vision works.