I remember reading that Hollywood played with faster frame rates and found a substantial number of people experience motion sickness.
Thomas Knox > Date: Tue, 18 Sep 2012 10:51:07 -0700 > From: jim...@earthlink.net > To: time-nuts@febo.com > Subject: Re: [time-nuts] Hi Power LED Light power supply... > > On 9/18/12 6:54 AM, Bob Camp wrote: > > Hi > > > > The shutter on a conventional movie projector is very much an on / off > > device. They run well below 120Hz. > > Actually, the typical movie projector uses a rotary shutter which runs > at twice the frame rate (e.g. 48 flashes/second) and is hardly a fast > transition. > > The actual waveform is more like a trapezoid (imagine a narrow beam of > light going through a rotating disk with two sectors in it..) > > There's also noticeable movement of the film as the shutter is opening > and closing, however, your eye/brain is pretty immune to overall image > shifts, particularly when it fills the field of view: it's not much > different than handling the saccades of your normal eye movements. > > 24 fps is quite visible to most people (hence interlace on TVs to get 50 > or 60 fields/second) > > > > > > The phosphors in a white LED are at least > > as long persistence as those in a TV set. There are a *lot* of TV's out > > there that refresh at 60 Hz or less. > > > > Bob > > > > -----Original Message----- > > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > > Behalf Of Poul-Henning Kamp > > Sent: Tuesday, September 18, 2012 9:05 AM > > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] Hi Power LED Light power supply... > > > > In message <ac9e4c92327746d4a521facd35d9d...@vectron.com>, "Bob Camp" > > writes: > > > >> I suspect those same 120Hz sensitive people would not be able to watch TV > > or > >> a movie :).... > > > > I suggest you either carry out a couple of experiments yourself, or > > go a little easy on the irony. > > > > CRTs, and LCDs go out of their way to avoid flickering using physical > > or electronic persistence, whereas a naked LED wil happily flash > > up to several hundred kHz if you ask it to. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.