Why do you call Film Analog?

[Bob Bell]

So as I read more and more threads on this site I keep reading the term Analog in reference to Film. I am very confused by this as I am an IT Professional and Analog is the opposite of Digital (1's and 0's) only in the sense of data transmission or capture. Like how a Vinyl record has continously changing quantities (bumps in the grooves) and a CD is an organized collection of 1's and 0's.

Film is not electronic in nature but rather chemical so I do not understand why someone would use Analog?

I'm sure there are other words that are inherently confusing as it seems to be a trend in photography lately, such as crop factor

[roteague]

Just the way people like to label things. It is something we all do.

You are right, film isn't analog, it is chemical. And digital, really starts out as analog. The term "analog" came to be used for film only after digital cameras came out, and then used to mean "not digital". Digital cameras, really are signal processing devices, which capture an analog signal, then convert them to digital.

[Alan Davenport]

There is no technical reason why "digital" must contain only 0's and 1's. It could as easily contain 1's, 2's and 3's, or any other number base. However, what is important is that digital can only have certain discrete values -- a bit can contain a 0 or a 1, but nothing in between, such as 1/3.

Film is not limited to discrete quanta; a point on a negative can contain not only the exact values that correspond to the digital values 0, 1, 2 ... 255, but also any value in between. Film is analog.

Now that "crop factor" thing is just insanity rearing it ugly head...

[Helen Bach]

The image on a piece of film isn't an analogue of an image, it is itself an image. That, to me, is a defining property of film. The discrete/continuous argument appears to be irrelevant. Just my opinion, of course.

Best, Helen

[N Dhananjay]

You could build an argument for film actually being digital - any grain of silver is either on or off (0 or 1). In contrast, a pixel on a monitor can be a larger number of shades of grey (e.g., 256 shades of grey) - that is, of course, still a discrete number of values.
I hink the analog thing is just a carryover from vinyl versus CD days - if something is not digital, it must be analog. So, if digital photography is digital, film photography must be analog.
And so the tiger chases its tail...;-)
Cheers, DJ

[Robert A. Zeichner]

The use of the word analog to describe older technology in general was almost unheard of before the advent of digital technology. Digital became the new way to express certain values in such simple terms (those ones and zeros) that it made possible, recording and transmission of that simple data so we could later convert it back to something that closely resembled the original picture, sound, whatever. Exact copies of things digital could be made and so reproductions of the original were now possible without the degradation associated with the old ways.

Before the digital age, we almost never needed a label to describe phonograph records, photographs, written words, etc., we didn't seem to need the word analog. Now it appears we need it to contrast things that are relatively new (digital this or that) to the things that were.

Why analog? Something that is analogous is something that changes in ways very similar to other seemingly unrelated things. An example: Sound which is mechanical energy, wavelike in nature, can vary in frequency (pitch), amplitude (loudness) and phase. Those changes can be expressed as electrical values (appropriate since electronics are used to capture, record and reproduce sound) that follow every change in the original sound very closely. The electrical values are analogous to the original mechanical energy.

In photography we deal with light of different intensities and colors of different hues and saturations. All these things are what we perceive when we observe a subject in real life. Film is designed to capture these attributes in a constantly variable fashion. The intensity of the light will determine the density of the negative, which will in turn determine the tones reproduced on the final print (subject to our darkroom manipulations, of course). The negative density is analagous to the original subject.

We never needed to make mention of this before we had a new way (digital) to express these values.

[Stan. L-B]

Interesting thread, excellent answers.

[Helen Bach]

...

In photography we deal with light of different intensities and colors of different hues and saturations. All these things are what we perceive when we observe a subject in real life. Film is designed to capture these attributes in a constantly variable fashion. The intensity of the light will determine the density of the negative, which will in turn determine the tones reproduced on the final print (subject to our darkroom manipulations, of course). The negative density is analagous to the original subject.

...

Doesn't that just land you back to DJ's tail-chasing, because such an analysis could just as easily be used to prove that B&W film was digital? It is not continuous, it is discrete. Than you can debate whether your tail is chasing you, or you are chasing your tail. Is the thing on film a representation of the subject, or a representation of the final image?

All this seems completely remote from my concept of 'the image on film'. Film appears to have been called analogue for no better reason than it is not that which is commonly known as digital photography. The lame and lazy way. Defined by what it is not, rather than what it is. No thought necessary. But it is brief, and its meaning can be guessed at quite easily. Damn.

Best,
Helen

[Steve Kefford]

...You are right, film isn't analog, it is chemical. And digital, really starts out as analog....

<<of or pertaining to a mechanism that represents data by measurement of a continuous physical variable>>

The key is that digital measures discreetly, whilst film measures contiuously. Therefore, film is analog.

Steve

[Ken Lee]

Straight lines (digital), when examined under magnification, are seen to be composed of many short curves (analog). Curves, when examined closely, can be seen as a series of many short lines.

There is a Buddhist term: "dependent co-arising". It suggests that in Nature, qualities define one other, and never appear alone. Tall and short, hot and cold, up and down, etc. are relative to one another. The same is true of analog and digital.

There is no such thing as a point, and no such thing as a line. Similarly, there is nothing that is purely analog or purely digital. Like points, lines, and curves, nobody has ever seen one - but they are helpful abstractions.