Film noir is one of the more interesting film genres because in a lot of ways it only exists as a collection of qualities identified after the fact. Film
noir exists as a very specific approach to telling certain types of stories about urban alienation and crime, many of which were forced on the filmmaker because of the production code of the period. This forces them to be highly stylized, and the post-modern hyper realization of today's cinema has often taken those qualities and amplified them. Shooting a wedding in film noir style is about as far from the original format as you can get, but may be an interesting way to approach an otherwise boring set up. Here are a few tips on shooting a wedding in film noir style with special attention to the aesthetic aspects of this genre.
One of the most identifiable aesthetic elements of the film noir style are the Dutch angles. A Dutch angle is a canted, or slanted, camera angle that leaves the perspective off balance. This may force it to lean in one direction or the other, but essentially avoids sitting straight. This is done to heighten the tension or give a sense of unbalance to the viewer, especially since there is a lot of moral ambiguity in film noir. This is easy enough when shooting a wedding in film noir style, and just choose to use Dutch angles at different points as a way of bringing up the energy as the wedding proceeds.
Film noir is nothing without lighting, and you may want to take a look at a lot of examples. Usually this means a lot of dark areas with very specific, moody, low key lighting on the subjects. It is harder to accomplish this kind of lighting scheme when you are filming in an active event that you do not have complete control over, but you may be able to station lights on some of the guests and on the alter. This will allow you to use a very high contrast lighting set up on the bride and groom and make sure that the background remains much darker.
Color or Black and White
Conventional film noir, such as the Maltese Falcon or the Big Sleep, were in black and white. This is because this was the standard film stock of the time, but since film noir's style developed out of necessity it is often important to maintain this. There are a lot of modern film noir examples, such as the films of David Lynch or Florida noir films like Palmetto, and you can look to them to find a way of using saturation and heavy reds and blues to accent a film noir feel. There is no right answer for whether or not you should use color or black and white for your film noir wedding, but since weddings tend to use a black and white color palette you may want to try it out when shooting a wedding in a film noir style. You may also want to try isolated colors, with black and white and a few selected hues coming through like the red of lips. This may take longer during color grading, but it is a nice effect anyway.
Source: Author's own experience.