It’s not by chance 60fps. It was chosen because power grid in USA is 60Hz, so it was easy and cheap way to synchronize frames without having additional timing hardware. As for 59.97, that was a 0.1% slowdown introduced when color TV was added to prevent cross-talk in chroma channels. Weird solution but it worked out fine. Today there’s no reason for sync anything with power grid but 60 is still a very convenient number as it’s easily divisible by many others.
Funny effect, though - many cheap electronics (think coffee makers and microwave ovens) use the line frequency as a time base. Taking a 60Hz or 50Hz appliance and plugging it into the other causes the clock to be off.
Not only that, but the grid frequency is not perfect and oscillates a bit constantly.
Investigators can then take the background electrical noise in audio recordings, look at the spectrum, and pinpoint the moment in time they were recorded based on the specific oscillations heard.
Huh, now that is interesting - our microwave’s clock continually edges forward until it’s a few minutes out from the oven clock right next to it. I wonder if that’s why. I’m in the UK and as far as I know, all our appliances are too, but maybe not?
That's probably just fluctuations in the line frequency and the method for keeping time varying between the two (one might use a crystal that drifts). Being on the "wrong" frequency will have it shift by hours every day. I had a (US/60Hz origin) microwave in my apartment in Bonaire (50Hz) last year that never seemed to have the right time, and when I did the math I realized it was the frequency - it was behind by ~4 extra hours every day (50/60 x 24 hours).
MeanEYE@lemmy.world 10 months ago
It’s not by chance 60fps. It was chosen because power grid in USA is 60Hz, so it was easy and cheap way to synchronize frames without having additional timing hardware. As for 59.97, that was a 0.1% slowdown introduced when color TV was added to prevent cross-talk in chroma channels. Weird solution but it worked out fine. Today there’s no reason for sync anything with power grid but 60 is still a very convenient number as it’s easily divisible by many others.
skullgiver@popplesburger.hilciferous.nl 10 months ago
MeanEYE@lemmy.world 10 months ago
I thought modern cameras compensate for that. Apparently not.
Overzeetop@kbin.social 10 months ago
Funny effect, though - many cheap electronics (think coffee makers and microwave ovens) use the line frequency as a time base. Taking a 60Hz or 50Hz appliance and plugging it into the other causes the clock to be off.
kadu@lemmy.world 10 months ago
Not only that, but the grid frequency is not perfect and oscillates a bit constantly.
Investigators can then take the background electrical noise in audio recordings, look at the spectrum, and pinpoint the moment in time they were recorded based on the specific oscillations heard.
sanguinepar@lemmy.world 10 months ago
Huh, now that is interesting - our microwave’s clock continually edges forward until it’s a few minutes out from the oven clock right next to it. I wonder if that’s why. I’m in the UK and as far as I know, all our appliances are too, but maybe not?
Overzeetop@kbin.social 10 months ago
That's probably just fluctuations in the line frequency and the method for keeping time varying between the two (one might use a crystal that drifts). Being on the "wrong" frequency will have it shift by hours every day. I had a (US/60Hz origin) microwave in my apartment in Bonaire (50Hz) last year that never seemed to have the right time, and when I did the math I realized it was the frequency - it was behind by ~4 extra hours every day (50/60 x 24 hours).
MeanEYE@lemmy.world 10 months ago
Yup.