A short stroll into non-existence

An analogue, or traditional, photograph is created by the reaction of light with a piece of light-sensitive material (film), made visible through a chemical process. The result is a usually permanent negative or positive, which is visible to the human eye simply by holding it against the light.

A digital image is also created by the reaction of light with a piece of light-sensitive material. In this case, the light-sensitive medium is an image sensor, which reports the captured image to a computer processor. The result is a sequence of electromagnetic impulses, which are stored in the computer’s memory and can be written to a magnetic medium.

Crucially, the digital image is not permanent and requires an additional technological process and computer hardware to be made visible. It can be wiped without leaving any traces.

On a philosophical level, this creates a problem:

The analogue photograph is actual and real (it exists – you can see it, touch it, pick it up, etc.), whereas the digital image only exists in the form of electromagnetism and only as a different form of itself, i.e. a numerical description, which instructs a computer to carry out certain processes. This process happens every time an image is viewed.

If an analogue photograph is destroyed, by cutting it into pieces or burning it, for instance, it still exists because it leaves traces in an altered form. The digital image can be deleted from memory without leaving any traces, as if it had never been created.

If something can be destroyed so completely that no trace is left, can it ever have existed?