Not all of us have appple quick time to run untitled.mov
I did this gif as a aid to your posted format, Dave
Most of the time I think Apple has a better video output
I started with apple long ago but never made it to the mac
so I dont know all the in and outs of is Mac OS
Now
answering Peter's question from a pc point of view?
I have 3 thoughts to add
1} I think, in his case, it maybe the 3d setting of the graph card, if his frame is 10 fps and above for a video 1032 x 774.
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2) or he may not have the right video grabber or using the right movie format for getting a constant 10fps and above.
pic_0079.jpg
3) or if its random and drop frame when he records
his machine maybe doing things in the background
Task Manager
Change your SU or Recorder, set priority, to high or real time
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