What is reportage photography
Reportage photography is a more objective record of an event through photography. I have heard it being described as giving vision ‘to’ an event, while more artistic styles give the photographer’s vision of an event.
How does one create a reportage photograph? Well, by it’s objective nature I would not add or remove elements of a scene that were not already there, both before and after taking the photo.
Reportage image processing ought to be treated a similar way, no drastic changes that may alter the way the image is percieved. Adding global adjustments such as exposure, contrast, saturation and white-balance may be excused as the camera may not have captured a ‘true’ image as seen by the human eye.

Reportage wedding photography
I’m a wedding photographer known for my reportage style. I aim to capture a mostly factual and neutral retelling of events with little to no interferance. There will be times that I have to step in to direct group photos, but this only takes half an hour, the rest of the day is uninterupted candid photography.
What is the difference between candid, photojournalistic, documentary and reportage wedding photography? Honestly, they all pretty much mean the same thing.

Sources
Documentary photography is a style of photography that provides a straightforward and accurate representation of people, places, objects and events, and is often used in reportage- The Tate
Documentary photography usually refers to a popular form of photography used to chronicle events or environments both significant and relevant to history and historical events as well as everyday life. It is typically covered in professional photojournalism, or real life reportage – Wiki
Reportage wedding photography is when your wedding day is unobtrusively documented in an entirely natural way. Nobody will tell you to do something again or ask you to laugh on cue. Instead, the whole day is captured as if the photographer was a fly on the wall. The wedding literally becomes like a story, taking you and everyone who looks at the pictures back to those moments, as they happened. – Kristian Leven