The format of a traditional Christian church wedding service, or civil ceremony, is more or less standard. In the case of a church wedding, the bride and her father will be met at the door by the priest in charge and there will be a pause of a few minutes while he or she speaks with them. During this period, the photographer may be able to snatch a few pictures before moving to the front of the church to record the bride's walk up the aisle to the altar. The bride and her father may be preceded by a flower girl or boy, and followed by a maid of honour, however many bridesmaids are in attendance, and perhaps a couple of pageboys. Where there is only a single photographer, this procession must be photographed from the altar end of the aisle. Such shots are not the easiest to capture because the bridal party are continuously moving towards the camera and focus must be grabbed in the same moment that an exposure is made. Another approach is to focus on a particular guest or row of seats and fire the shutter when the bride reaches the same point. The photographer needs to move away before the bride reaches the waiting priest.
Once the service is under way, the photographer must move to an unobtrusive position from which a clear view of the couple is possible. The couple may kneel or stand at various points during the service, and images must be captured at key moments wherever possible. A zoom lens, perhaps 80 - 200mm for a full-frame 35mm DSLR, is probably the best bet provided it has a wide aperture and the light and ISO setting make an acceptable shutter speed possible. Some priests will not allow the use of flash. Others will find it acceptable provided it is not intrusive, or perhaps not used during the vows.
If it has been agreed that the photographer can move around during the service, it is obviously important to do so unobtrusively and at appropriate times such as during readings or hymns. When the couple move to the vestry, or wherever the register is to be signed, the photographer must go with them and be prepared to organize a mock register signing once the real signing has been undertaken. This may involve setting up an appropriately positioned table and chair, and arranging the bride's bouquet and so on. Bear in mind that the whole congregation is awaiting completion of this process. The photographer should then leave before the newly-married couple so as to be at the back of the church to photograph the recessional. It may also be appropriate to stop the couple at the church doors and photograph them leaving the church, perhaps from both inside and outside.
Never overlook the many other opportunities that arise during a church service. It may be possible to get a few candid shots of the bridesmaids, flower girls and pageboys, as well as key members of the two families. Shots of the priest, the readers and even the organist or bell-ringers may also be worthwhile.