Posted on March 30, 2015. The following article has been registered with the United States Copyright Office and replaces the first draft of The Photographer's Resolution 2015, posted on August 18, 2014. Last update, April 25, 2021. For any information, contact: Copyright © 2014-2021 by Luigi Cassinelli. All rights reserved.

The Materia et Lumen Criterion


What is a photograph? The definition of the word photograph must be grounded in an empirical analysis, since photography originates in the discovery of the natural interaction between light and matter (the property of silver compounds decomposing to metallic silver when exposed to light) and is based on optical and chemical technology. Photography is not an arbitrary evolving concept, nor is it an abstract postulate. Photography developed from J. H. Schulze's discovery and became available with the invention of J. N. Niepce.

Article I - Definition of the Word Photograph

A photograph is a material and permanent, original trace of the light conveyed by an optical system, generated in the instant where light, the photographer’s interaction with his or her environment, and matter connect at the same time. The term "trace" should be interpreted with its existential meaning: an indication of the existence of something. The term “original” helps us to assess the unique genesis of the photograph, and consequently to differentiate a photograph from its reproductions.

Article II - Printing and Publishing Photographs

When we reproduce a photograph, whether by publishing or by printing it, we honor our audience by submitting, to the best of our abilities, a fair reproduction of the photograph. The unfaithful reproduction of the original interaction between light and matter is an act of manipulation. Any deceitful rendering, for example by not mentioning an act of manipulation, is an infringement of our criterion.

Article III - Semantics about Photography

The word "photograph" must be used exclusively for physical originals defined in article I (for example, exposed film negatives and film positives). We suggest the term "photographic print" for a print produced by projecting a photograph on a medium with silver halide based emulsion (for example, gelatin silver prints). We suggest the term "digital print of a photograph" for a print produced by means of computer operated devices (for example, ink-jets, lasers, and sublimation prints) and in compliance with article II. We suggest the term "digital scan of a photograph" to be used when uploading a photograph on the Web. We suggest the term "photography by" for giving credit, on any media, to photographers when reproducing their original photographs in compliance with article II.

Article IV - Information about Photographs

When we exhibit work that reproduces photographs, we honor our audience by submitting the available information about the original photographs.

A note to Article I - Definition of the Word Photograph

What document reveals a direct, permanent link with light? And which light are we referring to? These are the questions that lead our quest. The overwhelming and pervasive presence of digital images (on the Web, on magazines, on fine art paper, on a screen) doesn't help. Fact is, any published image rendered by software and constructed by machines could depict an authentic photograph, something doctored, or something entirely fabricated, pixel by pixel, dot by dot, with no link to a photograph. That said, digital technology is not responsible for confusion and manipulation; human decisions are accountable for ambiguity. Long before the advent of digital imaging, photography has been doctored in the process of printing.

Clarity can be found in the genesis of photography, the natural interaction between light and matter. Such a natural phenomenon happens for each photograph during the formation of the latent image, later revealed and delivered as a permanent document by the developing baths.

Digital scan of a photograph recorded with Fuji Neopan 1600 emulsion

Digital scan of a photograph. Fuji Neopan 1600 developed in Kodak XTOL in 2008.

© 2008 Luigi Cassinelli. All rights reserved.

What are the indispensable ingredients of this document? Light reflected by an environment, silver halides, an optical system, and the decision of one photographer. What is this thing? We call it a photograph. It is NOT an image like any other. It is a FOSSIL of one human experience. It is evidence, cemented by a natural phenomenon, of an irreversible human interaction within a real environment.

The following 4 sections will cover in depth analyses of what summarized in the criterion proposed above.

I. Technology

Photography is defined by the natural phenomenon of the interaction between light and silver halides; there is no photography without physical evidence of such interaction. For example, digital files alone cannot bear any photographic evidence, since they are mutant entities, by design.

The Peerless Invention

Each photograph is a natural phenomenon where the energy of light and the energy of silver halides generate one material record. Matter is essential to photography. There are many websites dedicated to sensitometry and to the properties of different emulsions. Our goal here is to remind that cameras alone are not sufficient to achieve photography. Leonardo da Vinci built a camera, but his camera couldn’t record anything. We need photographic cameras, where the output is matter, matter sensitive to light and capable of delivering one permanent record of its interaction with light.

Two Reasons Why Digital Files Are Not Photographs

digital image displaying a digital file recorded on perforated tape

Reason one: digital files are recorded by machines, not by the direct action of light. The image above shows the print out of a digital file, a code, paper perforated according to instructions. This medium is now obsolete, but it served the same purpose of our hard drives and flash cards, to store instructions for controlling the operation of machines. For example, right in this moment, your browser is reading instructions stored in a digital file (electronically stored in the server hosting this website) and is operating the pixels of your monitor. Each pixel of your monitor is lit according to specific instructions, thus creating an electronic image, but the image you see is an electronic simulation, not a photograph. If you press "print," different instructions will operate your printer, but drops of ink configured by a machine do not make a photograph either. Photographs are recorded directly by light itself. Conversely, the instructions written into digital files are created according to human protocols and recorded by machines.

Reason two: digital files are mutant entities. Still following the lead of light, we see how a digital file is not a photograph. Digital files are not material, they are not designed to be permanent, and they are not original traces of light; digital files are mutant by design. An abacus can help us visualize the essence of any digital file.


The image on the left shows one abacus in a specific status. The image on the right shows the VERY SAME abacus in a different status. In a similar way, digital files are designed to mutate too (according to the instruction of software). The abacus displays different codes with different positions of its beads; digital files perform the same task by making use of the electronic properties of solid semiconductors (for example, RAM, hard disks). As there is no original status for an abacus, digital files do not have one, specific original status (01 or 10?); they are designed to store and discard numeric codes.

Right now the digital file that your browser is reading contains one specific set of instructions, but, at any time, those instructions might change. Digitalfile.jpg is not a permanent entity, simply because it is designed to be whatever we want it to be. It "says" whatever we wish. We can name it whatever we please. It can be stored into punched cards or into solid state components. It operates our monitors and printers so that we are happily surrounded by the images we covet, but it does not produce what light itself would record. It cannot be a photograph.

Now, let's have a look at the sensor of a digital camera.

visual analogy of a digital camera sensor

Digital sensors have outstanding properties; nevertheless, by design, they also have one fundamental limit. The signal sensitive to light that they detect must be translated into a numeric code; then, the code is stored as a digital file and the signal is discarded. The chalkboard with the small abacus on top should help to clarify. The chalkboard mocks the part of the sensor that is sensitive to light (the analog component), the abacus the digital one. The image on the right shows our sensor detecting someone smiling. The sensor translates the smile into the code displayed by the abacus. Then, the sensor detects a new signal, this time a sad face, and the sensor translates it into a new numeric code. When we use a roll of film, we produce separate, physical frames. In a digital camera, the analog element sensitive to light must discard its connection with light. The only output is a digital file. At this point, contact with light is lost; all that is left is a numeric code stored in a digital file. Once again, a medium that is mutant. Further, codes are designed to be processed by software; one code can produce many images, but not an original one recorded by the action of light. By all means, we do not deprecate the use of digital cameras; we differentiate the output of digital cameras, computer simulations of photographs, from authentic photographs. Digital sensors and photography are poles apart technologies; we assess their disparate purposes. Digital cameras are computers that translate the electric input of sensors into a code. The output of a digital camera is a grid of instructions, input for simulation software, but it has no physical link with light.

Numeric codes and digital files are fabricated; actually, we don't need cameras to generate digital images; we don't need photographers; we don't need someone smiling or feeling sad. As we create numeric codes just by moving beads on an abacus, software generates any digital image we desire. Such powerful software might intrigue fans of videogames and virtual reality, but it is useless for photographers. Fact is that without an original photograph, a digital file has no direct connection with a real experience; it is just an instruction, a numeric code capable to operate machines like monitors and printers. For this reason, digital files will never supersede photographs.

Photographic technology is rooted in one natural phenomenon: the attraction between light and silver halides. No matter how much we rely on information technology, we should always remember that it cannot and it will never replace natural phenomena.

II. Ontology

The essence of photography is rooted in one, specific moment: the instant where light, the photographer's interaction with his or her environment, and matter (silver halide) connect at the same time. This connection, created by the photographer's irreversible decision, generates the latent image that will be developed into one physical, permanent, and original document: the photograph.

The Heart of the Matter

By pointing to a specific moment we assess and honor the photographer's decision to record what he or she sees, through a chosen optical system, by trusting solely the instantaneous and independent action of light on matter. This is the heart of the matter; this is the point where our view differs from other assessments of photography. Digital and chemical retouching in the reproduction of an original photograph are forms of self inflicted illusions, of trivial denial, or of plain deception. Retouching motivated on aesthetic or conceptual grounds might serve the purpose of image makers, storytellers, animators, but it voids the direct link with light, the reason to exist of a photographer. On the same account, the boundary between the transient nature of digital imaging and the permanent one of photographic phenomena should be defined unequivocally. Obviously this doesn't mean we do not appreciate other crafts, technologies, codes, and freedom in creativity. What we do not agree with is the practice of selling simulations as real phenomena.

The Unique Bond with Reality

A photograph is a fragment of reality and it cannot be dissociated from it. This is because it is rooted in the natural phenomenon that takes place when light and matter react. The image we read in it might convey a message, and its interpretation is subjective, but what light actually records is something close to a fossil (citing Sontag), and its body is objective. No other technique demands such a continuous interaction with what is real, light first of all. Photography challenges our direct relationship with reality, a harsh test for our frustrations, one that alienates many from photography and explains the success of retouching techniques. Setting aside all frustrations and illusions, an important question should be posed: Which evidence do photographs bring us?

Photography is neither a representation, nor a reproduction of reality; reality is more complex and dynamic than a single clue. That said, each photograph is the result of an interaction that takes place within reality, and this is quite a monumental achievement. For example, a photographic portrait is not a "copy" of a face; still, it shows how the photographer and the model interacted in that precise instant. Photographs cannot differentiate actors from soldiers. Nevertheless, photographs are inestimable historical records of the photographer's life, his or her exploration and decisions, as experienced.

III. Semantics

Photography must be differentiated from other techniques by using semantics consistent with its etymology. Authentic photographic work is only the one directly recorded by light. For example, ink on paper is not photographic.

The word "photograph" has been abused by incomplete, vague, often wrong definitions. If we assess its etymology: "n. 1839, formed from English photo- light + -graph instrument for recording" (From the Chambers Dictionary of Etymology) and the initial definitions formulated by Daguerre and Sir John Herschel, we should not use the word "photograph" for something essentially different.

"Written by light" is not a sufficient condition for the definition of a photograph. By examining photographic work, we should be more specific and ask ourselves "Which light?" Point is that, today as two centuries ago, a print is not a photograph; since the light emitted by an enlarger is not the light that created a daguerrotype or a negative. Reproductions and originals are not the same thing. Thus, we differentiate photographic prints from photographs.

"Written by light" is not a sufficient condition for the definition of a photograph, but is a necessary one. By ignoring this fundamental point, in the last century, marketing executives invented a decoy: "digital photography." "Digital photography" is an oxymoron, and "analog photography" is misleading. Fact is that photographic cameras record photographs and digital cameras deliver digital files, mutant entities that have no link with real light. Wrong word choices foster ambiguity and manipulation. We don't say, "I ate an analog pear," unless we believe there could be a digital one. We don't say, "I enjoyed a digital flight;" we use the words "virtual flight" or "flight simulator." We also do not consider pilots those who just play with flight simulation software. Real pilots are the ones who have the skills to fly a real plane. We need a new glossary for a new invention. The output of digital cameras should be named "virtual photography," "simulated photography," or, even better, a completely new word.

IV. Ethics

As in the reproduction of any original document and work of art, an ethical criterion is necessary in the reproduction of photographs. It is essential to differentiate between a photograph and its reproductions (whether the reproductions are photographic prints or digital images published on the Web) and to reproduce faithfully.

Originals and Reproductions

To understand the difference between original photographs and their reproductions we must follow the lead of light. Gelatin silver prints (prints obtained from the exposure of sensitive paper to the artificial light projected through a photograph) are not photographs, since they are not records of the light reflected from an environment; they are recorded by the artificial light of an enlarger and they are affected by the work of the printer.

Photographs are permanently recorded; thus, any manipulation performed on reproductions of photographs (for example, by chemical or electronic retouching) voids the ontological value of the photographs. If we conceal the manipulation, for example by naming "photograph" the product of a manipulation, we create an impostor.

On this account, the very same question we ask about images on the Web is pertinent to printed work too. One example of ethical statement is what Helmut Newton wrote on page 29 of his book Work (Taschen, 2000): "Nothing has been retouched, nothing electronically altered. I photographed what I saw." Now, how do we know that any print, photographic (gelatin silver) or digital, is faithful to its photograph? There is no other way than examining the original photograph.

The following two examples illustrate how to abide by the Materia et Lumen Criterion.

Digital scan of a photograph recorded with Fuji NPH400 and its printed reproduction on the cover of Italian Elle February 1999

Left, digital scan of a photograph, Fuji NPH400 developed in Kodak C-41.

© 1998 Luigi Cassinelli. All rights reserved.

On the right, its reproduction published on the February 1999 issue of Italian Elle.

Digital scan of a photograph recorded with Fuji neopan 1600 and its photographic print

Above, digital scan of a photograph.

Fuji Neopan 1600 developed in Fuji SPD in 2010.

© 2010 Luigi Cassinelli. All rights reserved.

Below, photographic print, printed by Gianni Romano on Ilford Multigrade FB Classic Matt, in 2015.