The lighting is one of the most challenging aspects of getting quality interior architectural photos. In a studio with controlled lighting, the amount and color of a light is consistent and predictable. In a home – it’s anything but consistent.
There are four major lighting concerns when photographing interior scenes. The one that comes first to mind for most people is the quantity of light. In reality – in a room with no windows virtually any amount of light will suffice with a longer exposure. The big challenge with light amount is the difference between the lightest and darkest parts of a scene. This is called the dynamic range of a scene – and most of the techniques for interior photography have evolved to deal with this challenge.
The core of the problem is that the human eye can handle a greater difference between light and dark than a camera can. On top of that, the human iris adjusts seamlessly on the fly so a scene with extreme brights (say, an open window on a sunny day) and extreme darks (a shadowy area under a couch) can exist and make sense. A camera can’t handle as much – and it will either crush the darks to black or the brights to white.
The second problem is the color of the light. This is measured in Kelvin – and in short, the lower the number the more orange the light is. The opposite end of the scale is blue. So, a typical incandescent bulb is about 2850K, daylight is somewhere around 4500K, and the “blue hour” just before twilight can even be 7000K and up.
The weather plays a big factor here.. on a dark day with heavy clouds the exterior light can be as high as 6000K. Since it’s dark out – the interior lights (2800K, remember..) play a big factor. There’s a huge difference between 2800K and 6000K – and if you set “white” for the interior – the outside looks neon blue. Conversely, if you set “white” for the exterior.. the interior looks Mandarin orange.
A few years ago when everyone used primarily incandescent light all the light colors matched – 2850K give or take about 10%. In the modern era of LED bulbs, there can be a huge swing in colors – warm white are around 2850K and daylight (the ice blue kind) are near 5600K. It gets stranger with compact fluorescent bulbs – not only is there a big range in yellow/blue but there’s a heavy green tint.
Light isn’t the only thing that contributes – paint, flooring, leaves, and many other things that light can bounce off contribute to the lighting color swirl. Pop quiz – what color is the white ceiling in your room? Answer – anything BUT white. It’s whatever color light or reflected light is bouncing off of it! This is especially chaotic with some colors of red or blue. If the light is bouncing off a wood floor the red will appear very orange. The warm morning/afternoon light will neutralize blue exterior paints making them appear grey rather than a rich blue.
Speaking of bounced light – glare is another factor. When light shines off the floor it often will overload the camera sensor as if you pointed it straight at the light source.
What’s the answer? It really boils down to one of two ideas. Light needs to be either added or subtracted to make sense of it all. Dealing with just one of those lighting issues will often worsen other issues. Many solutions to dealing with the dynamic range issues don’t account well for color imbalances between different light sources and will even accentuate them leading to an image that’s simultaneously hot and cold with exaggerated warm/cool colors.
Addition of light means bringing in more light of the correct color. This is usually a flash solution for photography. When a flash is used for lighting, the amount and color is known and consistent. Helpfully – the flashed light is generally 5600K and is much closer to the color of the exterior light. Care must be taken to not create unrealistic shadows and harsh flash reflections. In Hollywood – they’ll even shine lights in windows to give the correct amount and color rather than relying on Mother Nature.
Subtraction means removing – so it’s eliminating lighting of the wrong color or amount. This could be through closing a blind – photographing on a day with nicer weather so the inside & outside colors are more similar, or use of a polarizer to control glare.
A polarizing filter will reduce glare and shine by reducing bounced light. This can be adjusted by turning the filter to moderate the amount of shine. Personally – I like some shine because I think omitting all makes surfaces look dead whereas shiny looks “new” and “clean”.
Shooting on a sunny day means the outside light temp (4300K) is much closer to the inside – and the outside contributes more light to the inside. Be careful of glare and bounced color though – the sun creates both of those conditions.
There’s also compositing that can be used. This is using ALL of those techniques to produce the best of all worlds. An ambient interior image is the most natural look vs. a flashed image and can be set to the correct white balance for the interior. An ambient exterior image can also be exposed correctly for the outside and for the correct color. Blending them later in Photoshop makes an “ideal” image that’s labor intensive but the best possible result.
As a final note – there’s an artistic preference that needs to be considered. Personally – I prefer a natural look that conveys the mood of the room. That means that a dark moody room will still be dark and moody with warm lighting. A bright white kitchen will be bright and white. If over-aggressive color neutralization is used it can tear the mood right out of the room and make it look dull.