I am often asked which is the best lens for wedding photography and there is no simple answer! it depends very much on your style of photography and how you like to work.
If you favour a very shallow depth of field where the subject is in focus but you isolate them from the background with a beautiful soft out of focus bokeh then prime lenses maybe the best choice for that style of wedding photography. with a typical prime lens usually being f1.4 -f1.8 you can produce soft creamy out of focus backgrounds and bitingly sharp subjects particularly if you are using a 35mm full frame camera be it film or digital. For an even more luxurious look to your wedding images the medium format look be it a medium format digital camera or back or 120 film camera will give you that soft dreamy look you see in high end wedding photography and magazine such as Martha Stewart weddings are often shot on a medium format camera with a prime lens shot wide open. A favourite lens choice when shooting medium format film is 45mm f2 and you will see a lot of pro wedding photographers shooting medium format film will choose Fuji400h and shoot with the 45mm f2 wide open for a timeless look to their wedding photography.
For 35mm full frame photographers then the choice for weddings is often a Nikon or Canon 24mm f1.8, 35mm f1.8 and 85mm f1.8 or for photographers with deep pockets and strong backs the extra expense and weight of the pro lenses may be worth their while with Canon, Nikon and Sony making full metal bodied pro lenses in the 35mm f1.2, 50mm f1.2 and 85mm f1.2 focal range.
If you want to travel light and shoot from the hip then a top quality zoom lens may be your preferred choice as a wedding photographer needs to move and act quickly to capture the decisive moments if shooting in a documentary style. A nikon 24-70mm f2.8 or 24-120mm f4 VR is often the standard lens of choice for many a wedding photographer. Combine this with a 16-35mm f4 and a 70-200mm f2.8 or f4 and you have the perfect combination of lenses to cover any eventuality at a wedding from a super wide angle lens of the largest for group shots to a 200mm telephoto to zoom in on expressions of guests during the speeches without them even knowing you are taking their photo.
Specialty lenses such as a 105mm macro lens may come in useful for detail shots of the wedding rings or guest cards etc as well as making a great portrait lens so this can of then be found in the camera bag as well, or if you don’t want the weight of yet another lens in your bag you could use a closeup filter which screws onto your existing zoom or prime lens and allows you to focus at much closer distances.