Re: Burroughs, Strobes (was Re: monitor refresh rates & epilepsy)

Subject: Re: Burroughs, Strobes (was Re: monitor refresh rates & epilepsy)
From: Richard Wentk (
Date: Mon Jan 17 2005 - 17:12:52 EST

At 00:58 18/01/2005, you wrote:
>jan.larsson wrote:
>>If I remember this now the Burroughs/Gysin Dream Machine had a frequency
>>between 8-12Hz (intended to correspond to the alpha waves of the brain).
>>I think you can find DIY instructions on the net, but it is *not*
>>receommended for anyone having epilepsy or similar problems.
>It's been a whiole since I read about Burroughs but I doubt that it was
>merely alpha -- I recall
>72hz as being the frequency of the strobe penlight (whatever it's called)
>in eye triggering

I find this hard to believe because persistence of vision effects make it
unlikely that anything faster than 25Hz will be seen as separate flickers.

Don't forget that movies, TVs and monitors flicker at these rates all the
time and people aren't for the most part rolling around of the floor
bleeding from their mouths because they've bitten off their own tongues
after seeing them. Some of that is due to phosphor/LCD persistence, but
even if you strobe with short pulses and hard edges the eye seems to smooth
out anything much faster than this.

None of the strobe designs I've seen go much above 20Hz. And lo - Google
says this:


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