Based on an article I just read over on Luminous Landscape...
A digital camera's sensor is an analogue device.
When light hits a pixel an analogue signal is generated (a voltage).
The voltage is proportional to the amount of light received by the pixel.
It is not until that voltage is processed by an analogue to digital converter does
that pixel (and the rest that make up your image) become digital.
Refer to the first diagram here: http://www.ausphotography.net.au/for..._White_balance
Film is digital in nature (or at least binary (on/off)).
A molecule of silver halide when exposed to light and is then developed turns black,
or it doesn't turn black, depending on various factors including, but not limited to,
the amount of light that it receives along with the amount of development.
Tone happens as a function of area, i.e. when the number of silver halide molecules
in an area are (say) 30% black and 70% not black then that area appears as a grey.
Confused? I hope so
Next time you see someone with a film camera, maybe suggest they switch to analogue?
So what other surprising facts do you know about photography?