The audio quality of a dictaphone wouldn't be good and it would be very noticable on the soundtrack when you used it. I would go for radio mics with discreet lapel mics on both the bride and groom (tell both of them that if they want good quality sound then this is the way it has to be done), don't be afraid to lay down some ground rules right from the start, you are the person doing the video not them. Also tell everyone to switch off there mobile phones before the ceremony starts as you certainly don't want the sound of The Dukes of Hazard on your sound track. Take charge right from the word go and also try and avoid a run in with the stills photographer!

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