In the opening sequence when Sundance shoots the gun belt off the card player, the film was cut to make the quick draw appear faster. You can see Butch's image jump across the screen in the background.
Katherine Ross, (Etta Place) was caught operating a camera, filming some footage of the arrival of the train carrying the "super posse". In the late 60s the US film business was strict, closed shop union (to a great extent it still is) and Ross operating a camera was against every rule there is. Several senior crew members demanded her dismissal from the film but producer John Foreman and Unit Production Manager Lloyd Anderson, aware of the fact that a lot of scenes with her in it would have to be reshot at absurd expense, argued for a compromise to which the union agreed - none of the footage she shot would be used (it wasn't) and she would be asked not to be on set while scenes in which she was not involved were shot. Her gender was totally irrelevant to the issue. This is confirmed in William Goldman's excellent memoir, "Which Lie Did I Tell?"