The strange contraption called Camera obscura has captured the imagination of amateurs and experts alike for centuries. Before the invention of the photographic camera as we know it today (as our parents knew it, actually - for our cameras are altogether different), transfering an image a person sees before their eyes onto paper or canvas was no easy feat.
The renaissance genius, artists and inventor Leonardo Da Vinci was the first to describe a mechanism that would make the obstacles of linear perspective, foreshortening and proportion easier to conquer. Instead of slavishly measuring the lenghts, distances and angles of the tiniest details of an image, his idea offered a shortcut.
Tracing a scene projected onto a flat surface could help an artist bypass a lot of hard work and simultaneously serve as a learning tool. This was later to be perfected and used by artists as well as photographers for centuries, often maligned as a way of cheating, yet mostly considered an extremely useful tool.
The pieces of the Old Masters, with its spellbinding textures, its elegant shapes, its often superbly accurate depictions of the human form and real-life objects; masterpieces that continue to draw the attention of the art-loving public to this very day. Be it the early Renaissance pioneering achievements of Van Eyck, the innovations of Vermeer, or the fully formed academic language of Bouguereau, technical aptitude will always hold its appeal. One of the reasons for this is that not many people can achieve it. It takes a whole lot of talent, skill, patience and work to create anything even remotely resembling a Raphael or a Velazquez. So for us, mere mortals, the obvious question arises - how did they do it? Especially without the aid of photography. Or, even more commonly - what is the secret behind it? Because, if it can be done by such a minuscule number of people, there must be some sort of magic, a well-kept secret behind the curtains. Having existed since the 16th century as a separate mechanism, and the principles behind it having been known since antiquity, the Camera obscura has been around for almost half a millennia.
In Latin, Camera Obscura literally means "dark room". It is the name of a natural optical phenomenon in which the image of a scene gets projected through a small hole in the middle of said screen as an inverted image (usually upside-down) on a flat surface opposite of the opening. As the name suggests, the surroundings (or rather the inside of the camera obscura) have to be very dark in order for the image to be clearly visible. The hole needs to be small for the phenomenon to present itself, which, in turn, has given these devices the name of "pinhole cameras". They can easily be made at home. More advanced versions exist and have been around since the 16th century. They use optical lenses to give the projected image a sharper focus. These were the ones most probably used by artists like Vermeer.
If you'd like to make a camera obscura yourself without spending hundreads in cash, learning carpentry or becoming an optician - you can, easily so. In fact, you even have two options to chose from, one the size of your living room and the other more portable, comparable to a shoe box. Surprisingly enough, the former is somewhat easier to make.
Chances are that you already have everything you need at home for this little experiment. Your own living room might do just fine. A window and a wall opposite it are the two main elements of the mechanism. If the wall is white or at least light-colored, you should be fine but, if not, you might need to spread a white sheet or a canvas in order to create an even surface for the image to project onto.
The next thing you need to do is shut out all the light from the room. This can be done by covering the window with a piece of cardboard cut to fit. Next, create a small hole through the cardboard. With a bit of luck (and strong enough light coming from outside) you should be able to immediately see an upside-down image of the scene outdoors. By experimenting with different hole sizes, or adding a lense (one unscrewed from a flashlight can do the trick), you can see ways this affects the image and hopefully make it as clear as possible. But what happens when you want to take your camera obscura with you to the great outdoors?
First, obviously, a box is needed. A simple shoe box can do the trick but a more sturdy structure made of wood or plastic is much better if you'd like to have something even remotely durable. Cut out or remove one of the the sides of the box, fix a screen of tracing paper instead, and drill a 25mm hole on the opposite side. Cover the hole with kitchen foil and bore a neat round hole through it, no larger than the tip of a pen. When you take the box outside, be sure to cover the back side of it (the one with the tracing paper attached) with a thick blanket, as to shut out as much light as possible.
All this will, again, give you an upside-down image, much like that produced by the previously discussed room-sized camera obscura. Unless the box you've used is exceptionally sturdy and heavy, it will be somewhat difficult to trace the image without the whole contraption budging and thus making the projected image shift with it too. In order to rectify this problem, a mirror and slight alterations to the box are needed. Instead of removing the back side of the box, you need to cut out a rectangular hole on top of it, as close to the back as possible. Once that is done, you need to place a mirror inside, as shown on the diagram below, at a 45 degree angle, and only then seal the top hole with tracing paper. This will give you a better drawing surface, as well as an image that has been reverted back to its normal position by the mirror.
Now that you have your very own camera obscura - what can (and should) you do with it? Is it your ticket to becoming the next Vermeer or is it a contraption everybody knows about and will call you a cheat the minute they realize you're using it? Neither of the two, actually, and nothing nearly as dramatic.
If you are a student, an aspiring artist, an amateur, if you will, what the camera obscura offers is a quick and easy way to get the proportions and the outlines of your drawing right. By projecting a real-life scene or image onto a flat surface, it gives you an oportunity to trace it and thus save yourself the effort of measuring proportions, angles, and trying to get the lines right. While it is usually not sharp enough to use in portraiture (despite what David Hockney might say), it can come in handy in rougher figurative art, still lifes, or landscape. It can make your working process quicker, it can help you understand advanced concepts like perspective and foreshortening more easily, it can act as a shortcut. What it cannot do is replace perseverance, tenacity, hard work and study. For that is what realism of exceptional quality demands and all the cameras, measurement tools and such are but a bit of help along the way.
Editor's Tip: Vermeer's Camera: Uncovering the Truth behind the Masterpiece
It has long been speculated how Vermeer achieved the exceptional precision of drawing and accuracy of perspective in his works. It was often claimed that he used the Camera Obscura to enhance his realistic effects. But was it really so? Vermeer himself left no record of his methods, so the author is left to weigh the arguments of scholars both for and against the artist's use of the mechanism. Steadman does conclude that Vermeer did use it based on various peculiarities found in his paintings - the illusion of distance, the absence of sharp lines, slight blurring of image etc. - that can be ascribed to the inherent defects in this primitive device. Wether one considers it a final verdict or not, the book is a insightful and captivating read.
Featured images: 19th century Camera Obscura - via antiquesci.com ; Jan Vermeer - The Allegory of Painting (detail), oil on canvas, 1665-8 ; Two ink drawings by Canaletto, representing Campo San Giovanni e Paolo in Venice, obtained with a Camera obscura