Film photography is ANALOG!

Will S · Jan 24, 2006

I'm sure those of you who really know something about how silverhalide molecules really work can clear this up but it is my understanding that each individual "grain" of film is made up of individual molecules of silverhalide. These molecules are turned black or white depending on their exposure to light. (Which sounds very digital aka 1 or 0.) BUT those molecules are very tiny. The apparent density (or density variation I guess) of an individual grain is what determines how black or white the grain of the film is. All of those grains put together can be analyzed to get a Hurter-Driffield or characteristic curve. Each grain is not black or white, but distributed somewhere along this curve.

Last time I checked curves are analog.

So, I really don't see how saying "photography" is not analog just because the word itself can be analyzed to mean "light writing" has anything to do with the science behind it.

Digital imaging is a real bastardization since it takes the digital representation of light hitting a ccd, converts it to something analog (namely electricity) and then back to something digital (stored magnetic bits)... but I'm probably over simplifying.... But just think of the loss of information that occurs during all of that...

Thanks,

Will

Kirk Keyes · Jan 24, 2006

Film Photography is DIGITAL!

OK - I'll bite.

You forgot to go back to the initial step in photography, whether we are talking about film or electonic imaging. The image is made by capturing photons, either on film or some sort of detector.

Planck proposed that the radiant energy could exist only in discrete packets. The minimum energy packet is called a quantum. Einstein took that idea and assumed that the light was a stream of tiny energy packets called photons. When a photon strikes a metal its energy is transferred to an electron, this is called the photoelectric effect. This process is similar to what happens to the AgX in our film.

So if you want to get to the bottom of this issue, all film exposures are being made by individual, discrete photons. Counted in whole numbers, not fractional numbers. That would then be considered "digital".

Will S · Jan 24, 2006

Ahh, but those particles exhibit the behavior of rays as well. And rays are analog. (I think)

You are right I think that the reactions of the photons at the molecular level seems to be a on/off type behavior. I'm thinking that we (as humans) only care what happens at the level of grain though, and not at the level of the molecule.

I've learned a lot about film researching this, that is for sure....

Thanks,

Will

Kirk Keyes · Jan 24, 2006

Will S said:
I'm thinking that we (as humans) only care what happens at the level of grain though, and not at the level of the molecule.

Like with the duality that light exhibits, i.e. both wave and particle behavior, how can you truely separate grain level behaviour from the molecular level? The grain is just the aggregate of the molecules.

Glad you're enjoying your film research!

Kirk - www.keyesphoto.com

Kirk Keyes · Jan 24, 2006

Will S said:
Ahh, but those particles exhibit the behavior of rays as well. And rays are analog. (I think)

You're right, rays (wave behaviour) are analog, but they do not contribute to the photoelectric affect needed to make the exposure. For that, you need the particle form of light.

Helen B · Jan 24, 2006

What is the purpose of this quest for definition? To me, an image on film is not an analogue of an image, it is an image. An analogue of an image would be a voltage representing brightness for example, in the same way that an analogue computer might represent a flow of air by an electrical current.

Well, that's the way I look at it.

Best,
Helen
PS maybe the conceptual difference between discrete and digital would be clearer if we followed the French and used numérique instead of digital.

nworth · Jan 24, 2006

Will S said:
...

So, I really don't see how saying "photography" is not analog just because the word itself can be analyzed to mean "light writing" has anything to do with the science behind it.

Digital imaging is a real bastardization since it takes the digital representation of light hitting a ccd, converts it to something analog (namely electricity) and then back to something digital (stored magnetic bits)... but I'm probably over simplifying.... But just think of the loss of information that occurs during all of that...

Thanks,

Will

So why can't you use light to write on something other than a silver halide emulsion, whatever that may be? The terminology seems to work for a lot of processes, including digital.

Silver halide photography is just as impure as digital. Light ionizes a halide which reduces a silver molecule under the influence of the complex electrical fields of a colloid. Then the chemicals in the developer amplify the "signal" represented by the sparse, light-activated silver to produce the graded image using a very complex physical-chemical system. You're just more familiar with doing things with film. The digitization in digital photography is used to ensure accuracy, by the way. It also cuts costs. It is entirely possible to store the electrical signals as analog, but you probably would not like the results.

More along with the title of this thread, many users now mix analog and digital in various ways, and they are glad they can. Commercially, it has become most economical to take a digital image (either directly or from a scan of an analog (film) original) and print it on silver based chromogenic paper. This has great flexibility and produces better prints in the commercial environment than the straight optical-chemical process. For specialty and fine art printing, many photographers use high quality digital scanning followed by software manipulation to tune and correct the image (similar to manipulation during enlargement, but easier and more versatile) and digital printing to produce a final image. Digital printing now has near-archival stability (as good as most routine darkroom work) and very high accuracy.

I'm a film photographer. I like the large images I get from my MF and LF gear. I think the quality of these images is better than what I could get with a digital camera. But I appreciate what digital can do, and I will use it when appropriate.

Will S · Jan 24, 2006

Helen B said:
What is the purpose of this quest for definition? To me, an image on film is not an analogue of an image, it is an image. An analogue of an image would be a voltage representing brightness for example, in the same way that an analogue computer might represent a flow of air by an electrical current.

Well, that's the way I look at it.

Best,
Helen
PS maybe the conceptual difference between discrete and digital would be clearer if we followed the French and used numérique instead of digital.

Maybe I was misunderstanding another thread, but there seemed to be an argument that APUG was a bad name since traditional photography is not analog, and that Sean should have named the site TPUG or FPUG or something.

I was just throwing out the idea that a lot of film photography seems to be very analog to me. Of course, I guess you have to rule out all of those physical interactions at the molecular level with the photons....

And I'm thinking of the term as an adjective not a noun, i.e., "Of, relating to, or being a device in which data are represented by continuously variable, measurable, physical quantities, such as length, width, voltage, or pressure." In the case of film and prints I think that the densities of the silver grains fits this definition very well.

Plus it is fun to find out how things actually work. Or how people think they work anyway.

Thanks,

Will

tim atherton · Jan 24, 2006

Kirk Keyes said:
Like with the duality that light exhibits, i.e. both wave and particle behavior,

I was just going to say - as far as I remember no one still really know if light is waves or particles... or what?

Kirk Keyes said:
The minimum energy packet is called a quantum. Einstein took that idea and assumed that the light was a stream of tiny energy packets called photons.

it's heartening that so much of this is still "assumptions"

Kirk Keyes · Jan 24, 2006

tim said:
it's heartening that so much of this is still "assumptions"

Einstein's original assumption, made in 1905, has certainly withstood the test of time.

It has stood the test of time so well that most people now pretty much considered it to be fact. But that's what's so nice about the Scientific Method, if someone comes along with a better assumption, and it meets the test of time better than Einstein's assumption, then we will adopt their assumption as fact.

discotex · Jan 24, 2006

Will S said:
And I'm thinking of the term as an adjective not a noun, i.e., "Of, relating to, or being a device in which data are represented by continuously variable, measurable, physical quantities, such as length, width, voltage, or pressure." In the case of film and prints I think that the densities of the silver grains fits this definition very well.

Plus it is fun to find out how things actually work. Or how people think they work anyway.

I'm no expert on physics but I'd agree that the above definition fits.

If one is to get pedantic you could also argue computers are analogue devices as the way they store the ones and zero's is a continuously variable format. E.g. the magnetic charge on the hard drive platter is not exactly 1 or 0. It is more on or more off.

The quanta argument is very similar just reversed. Personally I think the fact that in non quantum terms we are recording a continually variable amount of light via grains of continually variable size qualifies film as analogue.

Of course this is all academic as the word analogue in this context is really meaning "without the use of a microchip" which I would argue is the common perception of the word these days.

All IMHO of course...

..Matt

Helen B · Jan 24, 2006

Will,

You explained, in answer to my question about the purpose of this thread:
"Maybe I was misunderstanding another thread, but there seemed to be an argument that APUG was a bad name since traditional photography is not analog, and that Sean should have named the site TPUG or FPUG or something."

Thanks - now I understand the purpose. I've always considered that for something to be 'analogue' it has to be an analogue of something else, otherwise it just becomes another word for continuous, and the argument becomes one of whether film is discrete or continuous. So, if a film image is analogue, what is it an analogue of? To me, it isn't analogous of anything, it is the thing itself. The real, sensible thing.

The use of 'analogue' in photography strikes me as no more than a way of saying 'non-digital'. The word makes sense in motion pictures where we have analogue video, digital video and film. But isn't the use of the word analogue just a matter of personal preference, or at least intelligent choice based on the particular context? If the most important thing about the name of this site is that it is non-digital, then 'analogue' seems concise enough, though 'non-digital' might be clearer. In another context, 'light sensitive' might be the better expression, for example.

Back to the main plot. Surely one can accept the idea that a film image is discrete without it being digital? For example, the optical density may be created by a number of discrete grains, but it is not created by numbers themselves. Isnt that the distinguishing feature of digital: the representation of things by pure numbers, not numbers of things. There's an enormous conceptual difference between showing someone seven stones, and writing the numeral '7'.

If 'analogue' now means "without the use of a microchip", what word do we use for the original meaning of analogue?

Best,
Helen

DannL · Jan 24, 2006

Helen B said:
The use of 'analogue' in photography strikes me as no more than a way of saying 'non-digital'.

Actually you are correct. A person needs a background in electronics to fully understand the difference between "Analog" and "Digital".

Digital = using digits as pertaining to electronics, ie; Ones and Zeros, On and Off, High and Low.

Analog = Where an electronic device has an output that is proportional to the input. ie; analogous, a linear amplifier in a transmitter

A digital camera uses both technologies, Analog and Digital to produce an image likeness on screen or eventually printed.

A standard "film camera" takes advantage of properties in physics and afterwards chemistry to produce an image on film or paper or a coffee mug. Sorry, I think this website was misnomered. ;-) It should have been "The Non-Analog, Non-Digital Users Group" NANDUG.com ??? LOL!

roteague · Jan 24, 2006

DannL said:
A digital camera uses both technologies, Analog and Digital to produce an image likeness on screen or eventually printed.

Yes, a digital camera is in reality a sophisticated signal processor; the sensors measure the minute signals that are recorded to determine how light or dark an image is. Also, since each sensor is able to record just a small range of color, the processor has to determine the dominant color by looking at all the colors around it by using a very sophisticated algorithm.

Helen is right, Sean has said that his idea behind "Analog" was to differentiate from "Digital", not a strict scientific meaning.

vet173 · Jan 24, 2006

This is what happens when you start thinkin after you just smoked some good shit.

nick mulder · Jan 24, 2006

The distinction is made up by marketers, know-it-alls, zealots, boors, etc... f*&k'em I say

The differences or lack thereof basically come down to a very fundamental 'problem' if you will ... the difference between a universe that is continuous and one that is discrete.

If you follow the path of this discussion you will either end up with quantum theory or some heavy metaphysical debate

two fields that are far from completion (if you wish to beleive there is an end) in terms of some grand unified theory of wotnot and so forth ...

Papa Tango · Jan 24, 2006

Must be we have gotten bored with debating Rodinal, Amidol, and whatever holy grail of film is the flavor of the week. "Digital" photography is a dry process that uses solid state electronics to achieve its ends. Conventional photography is a wet chemical process that uses malleable materials to achieve its ends. Analog and digital are both electronic terms. Those of us who use non-electronic means to make images might more appropriately be called "visual chemists".

I suppose it is now time for some wit to become an armchair physicist and begin comparing the atomic changes in silver and bromine with silicon and carbon. Too much for me...

Pinch me when its over

Helen B · Jan 24, 2006

"...if you wish to beleive there is an end..."

Well, that's easy to clear up. There is most definitely an end: it is the little end. When eating a boiled egg it should always be at the top. I think we can all agree on that.

Best,
Helen

nick mulder · Jan 24, 2006

Helen B said:
"...if you wish to beleive there is an end..."

Well, that's easy to clear up. There is most definitely an end: it is the little end. When eating a boiled egg it should always be at the top. I think we can all agree on that.

Best,
Helen

eggs are great with toast,

so.... take your toast, butter it and append it (butter side inwards) to your cats underside

pick up cat and then drop cat

hows that for a more worthy conversation ?

(from farside if I remember correctly)

gnashings · Jan 24, 2006

Just like philosophy used to be the "love of knowledge", and philosophers set out in the search of all answers they could find - math, astronomy, etc, I see the possibility of photography becoming something else: a discussion of terms for the sake of terms, concepts for the sake of concepts... A whole new breed of photographer, who takes no pictures but endlessly discusses the questions of the "photographic condition"...

PLEASE TAKE WITH BIG GRAIN OF SALT

Peter.

juanito · Jan 24, 2006

Film is not an analogue device!!!

In elctronics analogue is the term applied to any device, usually electronic, that represents values by a continuously variable physical property, such as voltage in a electronic circuit. Take a look at a phototransistor: when it is hitted by a bright light it takes out a big voltage and if the light is dimmed it give us a low voltage, and that is continously over and over.

Film does not react that way. The action of light in a film is an acumulative process. Once a film is exposed the effect of light in the emulsion remains. You can't expose a film over and over.! It doesn't changes continously and proportionally as the light changes.

So it is clear that a film is not an analogue device!

Photo = light , graphos = writing

The pioneers of photography were right when they choose the name for this new way of making images.

Juanito

nspatel · Jan 24, 2006

A couple more cents . . .

I suppose the terminology of analog and digital refers more to the final medium inwhich the final data is represented. Both a digital image sensor and a film are taking analog signals in form of light and processing it. After film is developed, the various sensitized grains will become nucleation sites for silver, resulting in an image that is interpreted as an image. For the image sensor, the analog signal is processed through algorithms to interpolate the missing colors and apply some compression. The end result is a file in either jpg or tiff (digital) format that has to be interpreted by a computer to be displayed as an image.

If you project light through a negative it produces an image. I bet if you project light through a jpg file if doesn't produce much.

nick mulder · Jan 24, 2006

I'm sure someone here has the quote 'everything is analog, even digital' in their signature line :confused:

Zeno's paradox anyone :

http://www.mathpages.com/rr/s3-07/3-07.htm

"... Consider a ray of light ..."

Marco Gilardetti · Jan 25, 2006

(Here was a flamed paragraph about previous posts, in which little or no comprehension of quantum mechanics, energetic levels and condensed state of the matter is shown, and the inopportunity of reporting as religious truths sentences which are not fully and critically understood, regarding matters which are not mastered by the poster)

Back to subject: doesn't the fuss come from the usual anglosaxon habit of shrinking words, perhaps? I believe that "analog" doesn't come from the term "analogy" how most people here seems to think for assonance. Isn't it the short term for "analogic" or "analogical"? That is ana- greek privative suffix plus -logic, that is over-the-logic or non-logic, that is not based on a sequence of zeros and ones?

At least, so it is in most european languages: "analogico" in italian, "analogique" in french and so on; "analogico" non being the contrary of the philosophical term "logico", which is in fact "alogico" for academics or "illogico" in everyday language. I would be very surprised if the english term - it alone - would have another etymology.

eddym · Jan 25, 2006

Helen B said:
Will,

The use of 'analogue' in photography strikes me as no more than a way of saying 'non-digital'.

I guess that's what bothers me about the use of the word "analogue" to describe traditional film-based photography; it comes about only as a means to differentiate it from digital photography. Before digital, we never used the word "analogue" in reference to photography, so why do we do so now? It sounds to me like a defensive action, as if we are being forced to define our traditional process only in reference to the newer one. Personally, I prefer "film photography"

Film photography is ANALOG!

Privacy & Transparency

Privacy & Transparency