A reflector is used to bounce, or reflect, existing light. It’s a portable, flexible tool that can dramatically enhance the lighting in your photos. They are easy to manipulate and experiment with.
Most reflectors you’ll see will be a piece of reflective fabric stretched over a flexible ring. However, there are many different types which differ in size, shape, and color.
For portraits, a small reflector is usually suitable, and it will be easier to handle. Larger reflectors will diffuse light across a larger area, creating a softer light.
Silver reflectors work well for studio lighting. They won’t change the color of the lighting and out of all the reflectors, will reflect the most amount of light. White reflectors are a bit more subtle, and will typically have to be placed closer to the subject. Gold reflectors will create a warm glow, similar to sunlight.
A reflector can make a great fill light (a secondary light source, used to lighten or fill in shadows created by your main light). Try placing it on the opposite side of your subject from your main light, and use it bounce light onto dark shadows. You can also place it below your subject to fill in shadows under the nose and eyes.