In 1992, I went on a study trip to Italy, accompanied by a number of students from the AKI Academy of Fine Arts and Design where I was teaching at the time. We visited the Caravaggio exhibition in Florence. This exhibition impressed me so much that as soon as I was back home, I started adopting Caravaggio's style of painting. Not that I started painting naked Jesus figures, but whilst painting, I tried to find out what methods he used, i.e. the way he used paint to achieve the best effect. None of Caravaggio's paintings show traces of him having struggled with the material; it is as if the paintings were completed in one go. A truly wonderful painter. As I understood it, the theme of the exhibition was a study of the 'incisions' Caravaggio was said to have made in the still-wet undercoat. You could actually see these incisions during the exhibition. Every now and again the lights were switched off and the paintings were illuminated from the side so that the observer was given a good view of what were, in fact, small slits in the paint, surrounding a head or around a hand or a finger. They were like outlines really, quickly done and not very accurate. Then again, sometimes they were effective and precise, as in St. John's knee in the painting 'San Giovanni Batista'.
A catalogue was published to accompany the exhibition – a very special one, in my view. It contains X-ray photos, floodlight photos and infrared photos of nearly all the paintings displayed in the exhibition and gives you a good idea of the way Caravaggio painted them. All the paintings were studied thoroughly and a
chapter is devoted to each painting. According to Longhi, the art critic, the incisions were made "to indicate certain relationships in distance between the most important volumes, so that in each session, in a particular light, the painter could recapture the correct posture of the models." Be that as it may, you cannot find the correct posture of the model in the painting but in the model his or herself, for instance in the form of chalk lines on the ground or a mark on the table on which the model might have placed his or her hand. These are useful marks in that every time they allow you to place the model in the same spot and in the same position. Outlines are of no use on the canvas, you could then just as easily paint what you see. In my opinion, no painter can create perfect proportions in one go, and in such a way that the whole picture fits in like a photo by using just a few outlines. Take the painting 'Incoronazione di spine', for example. If you start painting from the line around Jesus' right index finger, it would be impossible to paint a perfect line that ends up exactly at the spot where the eyebrow is supposed to be.
You use these kind of lines if you want to put a photo in exactly the same place under a transparency. Painters use these lines for attaching a projected image onto a canvas. As I see it, what Longhi writes can only be true if we assume that Caravaggio made use of projections. And although I have never read anything anywhere that suggests that, to me this does not seem to be a strange line of thought. The X-ray photos in the catalogue show us that arms, legs, heads and ears were all painted straight away in the correct place, and no corrections were made. Exactly as you would do if you used a projector to project the picture you intend to paint onto the canvas. That would also explain why Caravaggio did not need drawings; the correct
proportions required to work realistically were already there in the projection.
In my opinion, Caravaggio used the camera obscura. So I constructed a man-sized camera obscura, using two strong halogen lamps to replace the Italian daylight. All you need to do is illuminate a room with group of people from above with this light and through a small hole of about 3 mm in diameter you have a complete picture of this group. Pictures in exactly the same atmospheric light as most of Caravaggio's paintings then appear on the canvas. Caravaggio worked in two rooms. In one room, fully illuminated by the Italian sun, he positioned his models in a certain setting, after which he went into another room, the camera
obscura, to look at and improve his composition. Where necessary, the people in daylight were given
instructions and he moved the canvas about to obtain the ideal perspective. Once the picture was perfected, he inscribed the essential outlines in the soft dark undercoat and any models who were not immediately
needed could relax. Then, he painted the model who was still standing with white paint. Using the incisions, he fitted the various figures into the composition one by one and subsequently completed the painting.

Ramon van de Werken
Dokkum july 1992