In article <000f01c0e813$edc97740$[EMAIL PROTECTED]> you write:
>Many years ago I read about a method of testing focal plane
>shutter speeds by taking a picture off a tv screen and counting
>scan lines. Does anyone know of this method and how it works? I
>have long since forgotten. Apparently it is quite an accurate
>method. I expect there would be some differences depending on if
>your TV is PAL or "Never Twice Same Colour" format.
The horizontal frequencies are 15625 Hz for PAL and 15750 for NTSC.
Your computer monitor has a much higher horizontal frequency, some
go well over 100 kHz. Mine is now running at 1024x768 @ 86 Hz,
giving a 70.24 kHz horizontal frequency.
If you cannot see individual scan lines on your monitor screen,
you can put a test pattern with a vertical ruler in the root
window (= the background) and/or use a lower resolution.
--
http://members.chello.nl/~j.schoone \\|//
Registered Linux user #78364 - The Linux Counter - http://counter.li.org
Assume nothing, expect anything.
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