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Film Photography is Analogue

This rant is in response to an article flicking around among film photographers authored by an artist, designer, illustrator and photographer from Chicago who appears to have a large cult following. Mine is a response based on my IT degree and a number of years as an IT professional. The author of that article, claiming film photography is not analogue, is wrong on a number of crucial points.

The place to start looking is basic first year undergraduate computer science (UTAS will reassure you that I graduated in December 2008. My marks were consistently in the top 5th percentile).

Really, the second place to start is the opposite of pedantry. Calling film photography by the term analogue is a social convention that shouldn’t make you feel offended or smart. It’s just what we call it. I’d suggest you make more pictures and enjoy your life. But otherwise… carry on reading.

A Photograph is the capture of an Analogue Wave

That author is wrong because he is trying to say that the process of information capture, stored on film (the picture), is neither digital or analogue but something else. I’m sorry but there is no “something else”; the only two ways you will store information is as analogue (continuous variable waves) or as binary (discretely sampled bits as 1s and 0s).

To explain. Light is an analogue series of waves, in the simplest of explanations. Or, to be more precise, a photon is a particle at rest (with a resting mass of zero) and displays the properties of a light wave while moving (where mass increases without limit as speed increases). Environmental (analogue) signal information passes through the camera’s aperture at a correct exposure onto the light sensitive material of film. Thus, the storage of the information, the picture, is a capture of analogue waves that enter the camera.

The primary difference between an analogue camera and a digital camera is how that analogue wave is captured and stored. A film camera attempts to capture a wave of continuous variable information. Please don’t email me to explain that light isn’t a wave, or that it doesn’t vary over time. Please resist. Please.

A digital camera takes samples from those analogous waves and stores them as 1s and 0s (which, read on a little later, is binary information). The digital camera uses mathematics to interpret the missing pieces of information to make up the stored picture. The mathematical term for this process is interpolation.

The confusion seems to come from the idea that the film picture is revealed and fixed by chemicals and therefore the photograph is “chemical storage”. That is scientifically untrue – you can choose your opinion but not your facts. The picture information is caught as a wave of photons (noting the dual nature of light) and then revealed on the film negative at a later date by developer and fixer chemicals, true. But if the information isn’t caught as the wave of photons collide with the film medium… then the bottle of developer must logically hold the picture – how else could my trip to the beach get across to the chemicals?

There are only two alternatives for captured information – analogue vs digital. It is ALSO correct to say film photography is a chemical process. It is. But it is incorrect to make the statement “film photography is not analog”. And it is entirely correct for somebody to assert that they shoot analogue photography… that is, they make pictures with a film camera (as opposed to a digital camera).

Computers Understand 1s & 0s – Binary

That author is also incorrect about his understanding of how a computer captures and stores information. If anybody wants to understand how CPUs work there is a classic 6502 CPU emulator free for download. This is what first year undergraduate computer science students explore.

A CPU is the dumbest tool on the planet. It only understands 1s and 0s (one level below machine language) and operates by incorporating a set of logic gates. The manipulation of these gates is tedious in 1s and 0s. You *could* sit there pumping in 1s and 0s but it would mean nothing of substance by itself. You need calculation to provide the computing functionality that makes a computer… well, a computer.

The CPU consists of a number of registers for instant memory and utilises RAM (Random Access Memory) for fast short-term memory and hard drives for long-term memory. The closer the memory, the faster the CPU can utilise that memory.

The CPU understands an instruction set (machine assembly language). This is a given set of very limited commands that says things like “put this item into register A” then “put that item into register A” then “add items in register A” then “put that number into register B”. It is one level above 1s and 0s but the computer knows how to quickly execute machine code. Assembly code is one level higher again – human readable versions of the machine code.

Assembly commands break down into those tedious binary 1s and 0s.

Computers Can Deal with other Languages Higher Up

That author is also confused by the previous point because he infers in the article that the computer can understand other languages than binary – I’m guessing he means octal base 8, hexadecimal base 16 and other numeric systems. But the science should be explained to clarify.

The computer as a black box surely CAN understand octal and hex. If you code them into a CPU as 1s and 0s (binary digits) and employed registers so the logic gates could understand the output, then the CPU can swallow a lot (not anything – read about Big O Notation for efficiencies – but certainly this). However, you could put it this way for better understanding.

Nobody is going to program hex into a CPU as 1s and 0s just like they won’t work in Photoshop in 1s and 0s. A software program will take your “numbers” and push that down a level to assembly code where it is easily digestible by the CPU. The CPU eats 1s and 0s. But it knows how to interpret and compile assembly commands down to 1s and 0s repeatedly at high speed so instead of feeding the CPU an oat at a time the programmer feeds it assembly language, the instruction set, small cup-fulls of 1s and 0s that give computers greater efficiency.

The perception that a CPU is a dumb object – which in a sense it is – can leave the impression that it is without structure. It comes with logic gates for calculation operation and command execution, registers for calculation (dealing with data) and access to a special language that it knows by heart – the instruction set. If you try to get computers to talk they better both share an instruction set. I hope that makes sense. Otherwise they could only communicate at the basest, slowest level and I’m not even sure how that would effectively work. I did a postgraduate MBA rather than following through with computer science.

This is Easy to Misunderstand so I Appreciate the Difficulty

I think the bit that surprised me most was when I pointed this out to Jake B (his original tweet has been deleted) who pushed this issue forward on Twitter. Rather than listen to science and the IT degree behind these words, he went ballistic that such a noob as I would dare question his authority as a cool kid of photography.

Now Jake B’s tantrum is kind of similar to global warming. The science is in on this one, it’s not about belief. You can have your own beliefs but not your own facts. This is how computers work in science. I have a degree in computing and my marks were in the top 5th percentile. It’s basic first year science and technology stuff. And being wrong should mean you’re interested in gaining knowledge… NOT a moment to have pride related anger issue.

The tweet film photography is not analog came past as a retweet from someone that I do did care to follow and in passing I corrected that mis-assumption because it was scientifically incorrect to my understanding as an IT graduate.

The catch-cry “film photography is not analog” had also been used for the last six months (or longer) to disparage other film photographers who didn’t know what analogue was… because we need in-groups and out-groups like a steak through the neck… and therefore it was entirely appropriate (and is entirely appropriate) to explain the science.

There are ONLY two ways to capture and store information that I’m aware of – as analogue waves versus digital discreet samples from the waves using interpolation to fill the missing information. It’s simple semester 1 of an undergraduate computer science degree.

Shooting on film is an analogue (analog if you’re an American) technology. It just is. There is no analogue vs digital vs other.

Update: 5 Feb, 2013
I may have brushed over machine language by referring to it as binary…. here’s the clearer picture. Binary for the CPU… Machine language are instructions (the instruction set saying add subtract etc) that are converted and fed into the CPU as binary. The next level up, assembly language, is a more human readable version of those machine language instructions. Then higher is your software program.

So the software program tells the next level down, that passes down, and down and into the CPU as 1s and 0s through the logic gates and VOILA you have magic!

Update no. 2: 5 Feb, 2013
I also find it interesting that the objection traces back to the chemical emulsions on the film so that it somehow means the film is not an analogue technology. An example used for analogue was good old magnetic tape, with the assumption that sound waves somehow hit magnetic tape and the waves themselves make the tape have sound. From How Stuff Works – magnetic tape:

The tape itself is actually very simple. It consists of a thin plastic base material, and bonded to this base is a coating of ferric oxide powder. The oxide is normally mixed with a binder to attach it to the plastic, and it also includes some sort of dry lubricant to avoid wearing out the recorder.

Iron oxide (FeO) is the red rust we commonly see. Ferric oxide (Fe2O3) is another oxide of iron. Maghemite or gamma ferric oxide are common names for the substance.

This oxide is a ferromagnetic material, meaning that if you expose it to a magnetic field it is permanently magnetized by the field.

So, magnetic tape also uses chemical reactions to capture the wave. It’s how analogue storage devices work. Similarly, the second example of a vinyl record – a sound wave doesn’t crinkle a vinyl LP record, there is a chemical-mechanical process in manufacturing it. Chemical because the LP is made of something, too. Again, How Stuff Works – vinyl record.

The process of making records has its roots in Thomas Alva Edison’s phonograph. First, a master recording is made, usually in a studio where engineers perfect the recorded sound. Then an object called a lacquer is placed on a record-cutting machine, and as it rotates, electric signals from the master recording travel to a cutting head, which holds a stylus, or needle. The needle etches a groove in the lacquer that spirals to the center of the circular disc. The imprinted lacquer is then sent to a production company.

There, the lacquer is coated in a metal, such as silver or nickel, to produce a metal master. When the metal master is separated from the lacquer, the resulting disc has ridges instead of grooves. The metal master is then used to create a metal record, also called the mother, which is then used to form the stamper. Stampers are just negative versions of the original recording that will be used to make the actual vinyl records.

A record isn’t made by yelling at a disk of record stuff. And a tape isn’t made from yelling at a tape of tape stuff [insert my best Kryten voice from Red Dwarf]. Neither are they processes of chemical capture or mineral capture . They are analogue technologies with processes of capture that should make film capture of photons make more sense in the context of analogue versus digital cameras.

Again, some people are over-thinking this. I used to have a computer text book from university that had these exact analogue versus digital examples. I think it was called Computer Confluence by Beekman and Quinn. My version was the old IT edition, I gave it to a recent school fundraiser. A rule of thumb is if you’re not capturing the wave with a device that turns it into 1s and 0s… by default, it’s an analogue device. It’s a simple test. The film camera is analogue… but feel free to edit the first paragraph on that Wikipedia entry.

Analog device is usually a combination of both analog machine and analog media that can together measure, record, or reproduce (emit[disambiguation needed]) continuous information, for example, the almost infinite number of grades of transparency, color (such as in photographic film, a photochemical recording media), voltage, resistance, rotation, or pressure. In theory, the continuous information (also analog signal) has an infinite number of possible values with the only limitation on resolution being the accuracy of the analog device.

*cough cough* not analogous… that’s an entirely other definition of analogue… just like a walking fly on a bench versus having to fly to Cooktown. *cough* A wave is analogous to other waves.

Update: 6 Feb, 2013
I’m sorry, but I had to laugh when I saw the amendment to that Wikipedia entry since I’ve written this post. The sources are (a) the blog post I just pulled apart as being scientifically incorrect, and (b) another blog post that asserts film is not binary, which detracts from the amended entry. Please, please… you could have at least found an engineering text or an academic article that explained what analogue is, what digital is, and how it works, how it’s captured and treated. That was just lazy… and I guess it’s a test of Wikipedia being self-correcting. Let’s watch. It’s *cough* called *cough* inventing your own facts.

Magnetic tape uses a chemical reaction as well, an example used in the questionable article to show an analogue technology. In fact, how would you have any process without chemicals? I don’t think the author understands an analogue wave and how each camera treats the information to record. Or that the Universe is completely made up of chemicals, for that matter.

Just whatever you do don’t Google analog university photography.

And don’t read pages 58-59 of Data Communications and Networking ed. 4 by Behrouz A. Forouzan – under the heading Analog and Digital Signals.

Hammer, hammer… An Ode to the Retro Delights of Analog Media … hammer. But, no don’t just believe me… go out there and have a look. A film camera IS an analogue device and photographic film is an analogue media. Really… go to Google Scholar, get out engineering books. Look at university slides. Something. But don’t say because I believe & my friend told me so on the Internet.

A nice explanation of what digital cameras do when they capture analogue signals and digitise them.

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About the Author

Steven Clark Steven Clark - the stand up guy on this site

My name is Steven Clark (aka nortypig) and I live in Southern Tasmania. I have an MBA (Specialisation) and a Bachelor of Computing from the University of Tasmania. I'm a photographer making pictures with film. A web developer for money. A business consultant for fun. A journalist on paper. Dreams of owning the World. Idea champion. Paradox. Life partner to Megan.

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