6 ms·

The spacial resolution of analog photographs is not at the scale of individual molecules. It is limited by the "grain" of the film [1]. Other factors include d

The spacial resolution of analog photographs is not at the scale of individual molecules. It is limited by the "grain" of the film [1]. Other factors include distortions from lens shape imperfections in the lens material. Audio tapes record their signal in magnetic domains. These are areas of tape the are large enough to be written and read. Much larger than anything approaching the scale of individual molecules. Sound recordings on vinly are similarly limited by other factors. To "read" the signal from a record groove a needle is dragged a needle through a v shaped groove. This needle jiggles up and down and left and right, hence the two channels in stereo. The time resolution of the signal (max frequency) is limited by the physics of the jiggling head. It's inertia prevents it from reading signals over a certain limiting frequency. Again, well before the molecular level. [1] http://en.wikipedia.org/wiki/Film_grain http://en.wikipedia.org/wiki/Film_grain [edit] - Changed momentum to inertia in the last paragraph.

delinka 14y ago
I figured my layman explanation would suffice. While we're in the realm of correct details, it's also worth nothing that with each use of a needle dragged through a groove (or even with magnetic tape dragging across all the bits in the tape machine) the surface is degraded and the original recording along with it. Less fidelity, more noise ... hiss, pop, crack Digital gives us error correction so that even when the physical media starts to degrade (taking the signal with it) our firmware and our software work out where the mistakes exist and attempt to correct them. Of course, once the signal has degraded beyond the point of recoverability, you "suddenly" have a catastrophic failure. (And this is why backups are important...)
mistercow 14y ago
A couple points to add to that: with vinyl, the recording process itself (for which there are several techniques) also adds noise. The recording head (in whatever form) is also subject to physical laws. The materials used at each stage of the process are also not ideal substrates. Hell, vinyl is a polymer, which means it's a big tangle of chained molecules. Even if everything else were perfect, it would not be possible to write data at a molecular scale into such a medium.

delinka 14y ago

I figured my layman explanation would suffice. While we're in the realm of correct details, it's also worth nothing that with each use of a needle dragged through a groove (or even with magnetic tape dragging across all the bits in the tape machine) the surface is degraded and the original recording along with it. Less fidelity, more noise ... hiss, pop, crack Digital gives us error correction so that even when the physical media starts to degrade (taking the signal with it) our firmware and our software work out where the mistakes exist and attempt to correct them. Of course, once the signal has degraded beyond the point of recoverability, you "suddenly" have a catastrophic failure. (And this is why backups are important...)

mistercow 14y ago

A couple points to add to that: with vinyl, the recording process itself (for which there are several techniques) also adds noise. The recording head (in whatever form) is also subject to physical laws. The materials used at each stage of the process are also not ideal substrates. Hell, vinyl is a polymer, which means it's a big tangle of chained molecules. Even if everything else were perfect, it would not be possible to write data at a molecular scale into such a medium.