On Feb 23, 2015, at 11:57 PM, David Woolley <david@ex.djwhome.demon.invalid> wrote: > On 23/02/15 21:23, William Unruh wrote: >> manual corrections are probably good to 1 sec. to get 1 sec at 2ppm is >> about 5 days per measurement or 10 days altogether. > > It's a long time since I did this, but 200ms is more like it (might have been > 100ms). You need digital clock that is, itself, synchronised, and you match > the rhythm of the ticks, then let one of them actually move the return key. > > You have to really believe in setting accurate time not just be following some > instructions, to do this.
Threshold of perception for a new stimulus is around 80 - 100 ms. Untrained reaction time thus tends to be somewhat longer, right around the timeframes you've mentioned. However, if you time things with a rhythm you can get to ~50 ms or better, and subconscious muscle memory for practiced skills can involve timing on the order of ~5 - 10 ms. (Think of a ping-pong player who understands spin and can target the corners of the table reliably, or a pinball player who can trap the ball on the flipper and then make reliable controlled shots.) Regards, -- -Chuck _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
