When shooting portraits on an overcast day, the sky can act like a giant soft box creating soft, even light.
You generally don’t have to worry about bright sunshine making your subject squint, dappled light coming through trees, or harsh shadows on your subjects.
However, because this giant softbox is positioned directly overhead, it can be hard to have anything other than flat lighting, catchlights can be hard to come by, and portraits can sometimes seem flat and boring.
1. Shoot from slightly above your subject.
When your subject looks slightly down or even straight ahead on an overcast day it can be hard to get enough light in their eyes to make the beautiful catchlights we strive for as photographers. However, if you can get higher than your subject by having them squat down, bringing a step-stool, or finding a hill or structure to raise you above eye level, they will be looking up at the sky. Suddenly you will find their whole eyes filled with light. If it’s too bright this may make them squint, but on the dark, overcast days typical in the Pacific Northwest at this time of year, this can make for a beautiful portrait. It’s a really easy thing to do with babies, and the flat lighting works so well with their sweet little faces, but it’s a tip that works for any age.
2. Use your surroundings to create directional light.
Light on an overcast day tends to be pretty flat. This can cause people to look somewhat flat and dimensionless. To create dimension, you can use anything in your surroundings — buildings, trees, a fence, etc. — to block some of the light in one or more directions to create directional light. You can also use a reflector, a scrim, or even a flash to craft directional light on an overcast day, but since I tend to shoot without an assistant I look towards existing structures to help me mold the lighting.
In this set of images there is a street and open sky camera right and a row of buildings camera left giving some shadowing and dimensions to her face. In the closeup she is turned slightly more towards the street (notice the orange building behind her) so while there is still some shadowing it’s not as pronounced as on the full body shot.
The same sort of thing can be accomplished in a more natural setting as well. These are taken on a sidewalk near my home. There is a fence and dense row of trees camera left and even though there are some trees camera right, there is also more open area and more light coming from that direction. In the closeup, notice the catchlights coming from her looking upwards a bit as well as still getting some shadowing from the fence/trees camera left.
3. Be thoughtful when including the sky in your image.
A dark, stormy sky can be as interesting in a portrait as a beautiful blue sky. That being said, a flat overcast sky often wants to blow out to white or turn a light gray, and can really take away from a beautiful portrait. Consider not including the sky at all in your image or conversely embracing the flat backdrop as an integral part of your image.
4. Consider adding a pop of color in clothing, props, or processing.
The gray skies and lack of sunshine can sometimes make an image appear dull. Having a brightly colored prop or article of clothing — such as a great hat — can add some interest and a focal point back to an image. Another way to make your subject stand out on a cloudy day is to make sure the background behind them is a fair amount lighter or darker than they are.
5. Watch your settings.
Since there is generally less light on an overcast day, you’ll want to watch your settings to make sure you are getting a proper exposure. Often you’ll want to bump your ISO to 400, 800, or even 1600 to let in enough light. Even then you may need to open up your aperture or slow your shutter. Just be careful not to let your shutter speed drop lower than you can easily freeze the scene in front of you when trying to get a nice sharp portrait.