Re: Measuring accuracy of camera time codes

From: Marco Langbroek (marco.langbroek@wanadoo.nl)
Date: Tue Jun 02 2009 - 23:03:39 UTC

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    George Roberts schreef:
    > I assure you my laptop can trigger the camera at a certain time greater 
    > than 1 second accuracy and my laptop can also have it's time set to a 
    > time more accurate than 1 second.  I have a typical ping time of 100ms 
    > round trip to the Navy time source so my error is no worse than half that.
    > 
    > - George Roberts
    
    PC's do *not* trigger very accurately. It depends on how many processes are 
    running in the CPU and which ones are given priority - and that is variable. So 
    *after* the clock has synchronized to a NISP the timig behind different 
    processes conducted by the CPU - such as triggering a camera is variable, 
    depending on what processes are running at the moment.
    
    Bottom line: forget about PC's as a way to trigger camera's at a very precise 
    timing.
    
    The best way is simply manual, with a wire release and a clock in hand!
    
    - Marco
    
    -----
    Dr Marco Langbroek  -  SatTrackCam Leiden, the Netherlands.
    e-mail: sattrackcam@wanadoo.nl
    
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    -----
    
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