Mise-En-Scene ("placing on stage" if you translate the French) is one of the building blocks of good filmmaking. Mise-en-scene includes everything that is in front of the camera; from interviewees to lighting to props and sets. Careful control of the mise-en-scene is one thing that distinguishes the pros from everyone else.
When you're behind the camera you're in complete control of what the camera sees and records and there's a literal laundry list of situations that can negatively impact mise-en-scene and blow a shot. Here's the top five mise-en-scene miseries that you'll want to be wary of:
1. High Noon Lighting
Gary Cooper looks great when he faces down Ian MacDonald in the 1952 classic High Noon. One thing the beleaguered sheriff had going for him was a Hollywood lighting team making sure the harsh shadows of the overhead sun didn't completely obscure his face. The sun directly overhead on a cloudless day presents some of the worst, most unflattering lighting conditions. People's eyes, recessed in their sockets, get lost in shadow. There are two ways to combat this - add more light, either from a lamp or a reflector - or move your subject into the shade. If you can't move your subject into the shade, you can bring shade to your subject by holding a large diffuser between them and the bright sun. The bigger the better. Lastolite and Photoflex make good ones, or your can go DIY with some PVC and a bed sheet.
2. Up the Nose
There are certain things that only an otologist should see and one of those is whatever's to be found on the inside of your subject's nose. If you're shooting up at a person on a stage, move back, raise your camera, or move to one side so that your subject's nasal passages aren't the main focus of the shot. Also watch out for this when shooting people who are laying down, you don't want the angle to be from their feet, but rather at their side.
3. Unflattering Backgrounds
When shooting that special birthday greeting your sister wants to send to grandma, don't get the dirty dishes in the shot, because grandma's going to call with a lesson in housekeeping. This goes for other clutter like half-empty drink containers, trash cans, and piles of paper. As a general rule, try and keep your background uncluttered. The typical interview subject may be oblivious to how the background can make or break a shot so some gentle guidance from the shooter's perspective can go a long way.
4. Shooting into the Sun
Backlighting a subject will lead either to an extremely blown out (too bright) background, or to your subject being silhouetted. The rule of thumb here is to position your camera b/w your subject and the light source. You'll also want to be mindful of very high contrast in scenes too; dappled light underneath a tree can be different enough in brightness to ruin a shot if someone's face is half in direct sunlight and half in the shade. The goal is to having more or less even lighting on the subject -- it's always a good idea to bring an onboard light for your camera for backup in a pinch.
5. White Balance
Different light sources have different color temperatures, indoor lighting tends to be warmer (more orange) while sunlight has a blue hue. Setting proper white-balance when shooting is the best way to make sure all your footage comes out looking color accurate. This especially comes into play when shooting people since skin-tones can range from jaundiced to oompa-loompa if white-balance if overlooked. Most cameras have decent enough auto-white balance settings but if you want to do it right just drop a white card in front the lens so it fills your frame and use the manual white-balance setting - then you're guaranteed accurate color temperature
If you've ever run into the above issues then you're well familiar with how big a hassle it is to fix them. Editing and post-production can only go so far and most times these problems can only be solved by taking a mulligan and reshooting.
One ruined shot can serve as a permanent reminder of the importance of exercising tight control over your shot and it's content. Avoid the pain of learning the hard way by always being mindful of the your mise-en-scene
