Why do you call Film Analog?

[roteague]

The language is, in the end, just a reflection of the way the brain works and that's why we will continue to have both digital watches and digital darkrooms.

The same reason people now call their cars "rides".

[tim atherton]

Why is an old style mechnical watch analog?

I believe it's because watches are an of analogue of passing time. i.e. the movement of the hands is an analogue of the movement of the sun (or the movement of the earth depending on where you stand...) etc

(this is analogue used in its main meaning, not the narrower secondary technical/electronic sense)

[Doug Kerr]

Hi, Bob,

So as I read more and more threads on this site I keep reading the term Analog in reference to Film.. . .
Film is not electronic in nature but rather chemical so I do not understand why someone would use Analog?

An analog representation is one in which some continuously variable physical property varies with, and thus represents, the value of another continuously variable property. For example, in a mercury thermometer, the height of the mercury column (a continuously variable phyiscal property) varies with, and thus represents, the temperature (a continuously variable phyiscal property). The one property is the analog of the other (thus the name). A mercury thermomenter is an analog instrument.

In an audio waveform, the instantaneous voltage on the circuit (a continuously variable phyisical property) varies with, and thus represents, the instantaneous pressure of the acoustic wave (sound wave). The waveform is an analog representation of the acoustic waveform.

By "continously-variable property" we mean a property that can take on any value over its allowable range. For example, the instantaneous voltage on an audio circuit at some instant, stated to to a precision of 18 decimal places, can be 0.200000000000000000 volts, or 0.200100000000000000 volts, or 0.200100000000000001 volts, all of which are different. And in fact it can be 0.200100000000000001000000000000001 volts, or any other value we can imagine (over the allowable range). We may not be able to distinguish them by practical measurement, but that doesn't change the fact that they are distinct.

By contrast, in a basic digital representation of an acoustic wave, a number represents the instantaneous pressure of the acoustic wave at a particular instant.

Now, to your question: in conventional negative photography, the density of the negative at a spot (a continuously variable physical property) varies (for a given lens aperture and exposure time) varies with, and thus represents, the luminance (brightness) of the corresponding spot on the scene (a continuously variable physical property). Thus a photographic negative is an analog representation of the luminance of the scene.

[George Kara]

Digital/Digitizing when used as a verb or adverb describes a sampling of wave amplitude using a binary unit of measurement. The "digital" in digital watch is used as an adjective modifying the noun "watch". The term "digital watch" holds no more meaning as a description than "shiny watch". There are all sorts of digital watches that are not only numeric.

To digitize an input or output is always a conversion to a finite binary unit of measurement. In other words the verb or adverb shouldn't be confused with the adjective.

When the doctor gives you a "digital rectal exam" the word digital is being used as an adjective. He/She most certainly won't be putting a camera up your ass. That may happen on the next visit. For this next exam your doctor may digitally photography your prostate. Perhaps if the doc is interested in astronomy he/she may also digitally photography Uranus!

In the proctologist office, separating your adjectives, verbs and adverbs may be significant.

George

[Marko]

The same reason people now call their cars "rides".

I prefer to think of it as the same reason they still call their image-taking devices "rooms", a thousand years later, give or take.

[roteague]

I prefer to think of it as the same reason they still call their image-taking devices "rooms", a thousand years later, give or take.

Yea, I suspect we won't even be able to understand the language spoken in a thousand years, just like we have trouble understanding the King James english today.

[Marko]

Yea, I suspect we won't even be able to understand the language spoken in a thousand years, just like we have trouble understanding the King James english today.

Probably not - a thousand years ago, English as we know it was non-existant and the Lingua Franca was Latin. Who knows which is it going to be in yet another thousand years... Chinese, maybe?

But in all fairness, I wouldn't blame our failure to understand each other on the language.

[Dave Parker]

But I guess that I'll get used to it.

Well at least you admit there is hope!

LOL

[David A. Goldfarb]

I don't usually use the term "analog" myself to describe traditional photographic processes.

As far as "APUG" goes, well, I wish it were called something else, but at least APUG is easier to pronounce than TPUG, FPUG, GSPUG, GSPTPDPUG, EtcPUG.

[Dave Parker]

As far as "APUG" goes, well, I wish it were called something else,

And all he said was "Hmmmmmm!"

LOL