I charge from the time I arrive at the initial location to the time I leave the reception. If there's a big break between the ceremony and reception I might consider a discount for that, but it's still a long day which deserves appropriate compensation. If someone wants to get picky about this I could itemize all the time I put into doing a wedding video and charge them 1.5-2 times what I do now, so it's not worth haggling with someone over how many hours of shooting are involved.