Pinhole Photography
Pinhole cameras provide us with personal wealth as a fetish, as alchemy of modernity or as a miracle and revelation of the close proximity of our perception
Photographic process
Involves passing light through a small hole. The smaller the hole will more clearly in the picture. We call pinhole and is designating the technique with which we create our camera. On the side opposite the hole will form the image of what we see ahead, and where to place the photosensitive material. It provides an infinite depth of field. We got the picture with a mathematical formula that measures the distance between the pinhole and focal diameter. We can make a simple cardboard box or timber. The exposure time will vary depending on the diameter of the opening.
Origins
The first news comes to us from the hand of the early research on the camera obscura in the V century BC Mo Ti, a Chinese philosopher was the first image with a pinhole through experiments on the propagation of light in a straight line. Philosophers like Aristotle refer directly to the mathematics of light, by the Arab mathematician and physicist Ibn al-Haitam which placed three candles in a row and a screen with a hole between the candles and the wall. So were mirror images. In the Renaissance it was used as scientific purposes in astronomy and reinforcing the drawing for Leonardo Da Vinci. In the modern era was used by archaeologists for their expeditions.
David Brewster, a Scottish scientist, is the author of the first picture taken with a pinhole camera. In the last decade of the nineteenth century in the United States, Europe and Japan sold more than 4,000 cameras by the result of mass production industrial production.
With the emergence of new technologies for analog cameras, the pinhole technique was abandoned in the twentieth century. Little by little they are uncovering more and more information and a general interest in the digital age through given before the prying eyes of many citizens.
Calculate exposure: aperture
Try adjusting the size of the hole according to our aesthetic needs. We already know that the smaller, higher resolution image get, and the circle of confusion will be bigger. We must avoid diffraction we can compromise the sharpness openings too small. It could also cause vignetting at the edges of the image if the diameter and thickness of the material because it passes all the light. We always try to use a material as thin as possible and make the needle hole with a simple, but very gently to get the best quality in our work. It is generally used aluminum foil as a beverage and then liman edges.
Mathematical formula
The Hungarian Joseph Petzval was first formulated an equation to calculate the diaphragm as the focal length.
D = diameter
f = focal length between the film and the opening
Y = wavelength of light
Recall that the diameter is known if we know the diameter of the needle we used to drill the brass. Just so we know the focal length is the distance between the plane of the hole and photo paper
If a camera has a diameter of 0.8 and a focal length of 80mm, f-number will be 160 (80 / 0.8). That probably become our output prolonged exposure.
Pinhole photography day
Is widespread evidence that this type of photography is reduced to the simplest expression through a complex process. In our days has revived the need to pay tribute to alchemists, scientists and mathematicians who had a strong research and aesthetic purposes today is to continue to move toward creative ritual almost do not want to see the end. For a long time this photographic technique becomes obsolete, but today is a trend in the more intimate world of photography.