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A only mark (sound marker, filming):
Usually it's not your choice anyway, you do put whatever the script supervisor wants onto the slate. The sound mixer will slate his own audio so you only need to say "A mark" and hit the sticks. If it's more convenient, you can common mark and that will go something like "A B common mark." If you're generally rolling multiple cameras but only roll one on a shot, you might want to call it "A only mark" just so it's known that B didn't roll.
http://www.cinematography.com/index.php?showtopic=47360&p=329090
A only mark (sound marker, filming):
Usually it's not your choice anyway, you do put whatever the script supervisor wants onto the slate. The sound mixer will slate his own audio so you only need to say "A mark" and hit the sticks. If it's more convenient, you can common mark and that will go something like "A B common mark." If you're generally rolling multiple cameras but only roll one on a shot, you might want to call it "A only mark" just so it's known that B didn't roll.
http://www.cinematography.com/index.php?showtopic=47360&p=329090
