[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Eclair ACL 25fps frame roll

That's what I was afraid of. But you know what, it's strange because I know
the 24 fps speed (using the corresponding crystal) to be right. (I have a
little electronic device conceived for measuring the speed of projectors
that counts the shutter openings in one second and shows that number divided
by two - because projectors usually have double shutters - and that gives me
a perfect 24/2=12. But I can't use that trick for 25 because it doesn't show
tenths of images). Could it be my 25 fps crystal that doesn't output the
right pulsation ? Then all I would need would be a new 25 fps crystal...

Nicolas Rey

le 21/11/01 14:14, Robert Latimer à themoviehouse@hotmail.com a écrit :

A 50hertz TV or video monitor is EXACTLY 25fps so unfortunately the
horizontal roll problem is with your sync motor.  This would soon be
confirmed by shooting sync sound and having the results telecined, as
depending on the rate of roll, your sound would fall out of sync within
about ten seconds.

You'd be surprised at how few motors actually run at the precise crystal
speed the manufacturer claims.  Certainly as the motor and the camera ages,
more problems occur.  It's probably best you get your entire kit serviced,
this may eliminate the problem.  If it doesn't, you'll have to plug in an
external sync for your motor (not so easy for the ACL but very easy with an
NPR) or an engineer who can tweak the crystal on the back of the ACL motor
so it can be slightly over or under-run.



This email was sent to: elroro@propagandaindustries.org

EASY UNSUBSCRIBE click here: http://topica.com/u/?a84xYK.a9svPI
Or send an email to: EclairACL-unsubscribe@topica.com

T O P I C A -- Register now to manage your mail!