Film is digital and digital is analog

[Jacques]

Yes that's right film is digital and digital is actually analog.

Either photons hit a particular grain of silver halide to alter its charge or they don't. So they either, are or not, on or off, 1 or 0, with no variables in between. Film is therefore a binary recording medium.

Moving on to digital the sensor responds to light by producing a continuously variable voltage which is then converted to an alpha-numeric value by an analog to digital converter. Therefore it capture images in analog.

Isn't science fun?

[one eyed jack]

But sir, does that mean film is still a superior medium over digital then?

[Jacques]

Yes.

[Sam Slater]

So the only real difference is the uniformity?

Grains of silver halide are of different size, thickness and angle to the light, and are also spaced out 'haphazard' (like grains of sand). Pixels are uniform in size and spacing.

So if you get pixels small enough, 'digital' -as we know it- would give an overall better picture than analogue -as we know it-, whereas analogue can produce a more accurate and better picture in areas where the silver halide grains are smallest and less spaced out (which will only be at certain points across the film, and not across the whole film as there will be places where the grains are larger and more spaced out giving and inferior image in those parts of the image).

So my conclusion is that as long as we can produce pixels -on a censor- smaller than the smallest silver halide grains then digital will always give a sharper image.

Colour accuracy is another matter though.

Another thing I've just thought about is 'light sensitivity', so the quality of the sensor has a lot to do with it's light gathering ability.

[strictlybroadband]

Yes and no.

You're right, film is digital at the molecular level. Still, it's far more fine-grained than any CCD so ar created.

But you're wrong, digital isn't analogue. The light falling on the CCD is analogue , and so is the electrical current produced, but the CCD's job is to convert the signal to numbers. Numbers are digital and digital is the opposite of analogue.

All digital I/O devices have some analogue qualities - a mouse is analogue when you move it around, but it produces a digital version of the movement.

[eroticartist]

Photographic images are optical which means light is used to make and project them.
Using optical fibres we may one day have faster computers it is said.
Mike.

[Sam Slater]

I know what Jacques means and actually see it as 'all' capturing processing is analogue.

Silver Halide does indeed get a on/off charge, but we call it analogue because the information recorded on film is never converted to a binary format. Jacques is probably saying that the on/off charging of the silver halide 'acts' like a binary format in it's nature, and thus 'becomes' a binary format on film.

I personally see it as an analogue format that 'acts' like a binary format!

As for digital censors.... Well again, the actual capturing of light is indeed analogue in nature, and the on/off nature of the censors indeed convert these instances into 1/0 formatting.

The + or - charging of silver halide imitates 1/0 binary formatting, but they're not the same thing. (they just work upon the same principles).

[fudgeflaps]

Well, that's modernity for you.

Most modern technology operates on this principle doesn't it? The capturing of an analogue signal and CONVERTING it to digital via an ADC more or less means the term 'digital' for all our showy 'digital' products is a bit of a misnomer! It's analogue packaged neatly.

Vive le analogue revolution! Buy an analogue watch. Use 35mm film, and go black and wjhite, look dead debonair and arty. Campaign for an analogue ipod, it will be a bit bulky though! Down with digital wardrobes!

[andy at handiwork]

Back to mono.