Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!pasteur!agate!eris!doug
From: doug@eris (Doug Merritt)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Fixing flicker, & future frame rate issues
Message-ID: <9028@agate.BERKELEY.EDU>
Date: 21 Apr 88 07:39:45 GMT
References: <11157@ut-sally.UUCP> <8528@agate.BERKELEY.EDU> <11182@ut-sally.UUCP> <8577@agate.BERKELEY.EDU> <1367@hubcap.UUCP> <3626@cbmvax.UUCP> <8712@agate.BERKELEY.EDU> <3641@cbmvax.UUCP> <884@gethen.UUCP>
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Reply-To: doug@eris.UUCP (Doug Merritt)
Organization: University of California, Berkeley
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In article <884@gethen.UUCP> farren@gethen.UUCP (Michael J. Farren) writes:
>and is, that the 60Hz strobe of the flourescent lighting was interacting
>with the 50Hz screen update on a low-persistance monitor, producing
>"beat" variations in the light input to my eyes.  [ ... ]
>BTW - this is an example of "true" flicker - changes in the light
>output of the _entire_ display, rather than the localized changes
>that are annoying in an interlaced display.

That's interesting, since it implies that any field rate that's
not synchronized to flourescent light frequency (equals line freq.)
will have flicker problems. If the beat frequency is low enough,
the field rate could be 2000 fields per second and you'd have flicker.
Hmmmm...

On the other hand, flourescent lights in *Europe* are 50hz, since that's
their line frequency. So a 50hz noninterlaced display in Europe
should not have a beat frequency problem with flourescent lights, right?
And yet Hedley said that it was in Europe that the problem was
observed. Strange.
	Doug Merritt		doug@mica.berkeley.edu (ucbvax!mica!doug)
			or	ucbvax!unisoft!certes!doug
			or	sun.com!cup.portal.com!doug-merritt