If you have ever worked with flash, you may have asked yourself, “when do I use ambient light and when do I use flash?” The answer, unfortunately, is not an easy one. If you have followed my photography for any length of time, you would have noticed I use a lot of flash, even in sunlight. There are a few occasions, however, when I will opt for ambient light over flash.
First, let me explain why I prefer flash. I like to have control over my lighting. When I use ambient light, I am at the mercy of the environment. If I am shooting outside, the lighting may shift from sunny to cloudy without warning. If I am indoors, there may not be enough light, or the light may not be where I need it.
When I opt to use ambient light, I am typically shooting environmental shots, where any flash would change the atmosphere of the shot. This may include landscape, street, and candid photography. I may also opt to use ambient lighting when it is staged itself, such as in a club or at a concert.
I recently encountered such a situation in a Dallas club. In most of the settings, I shot with one or two flashes, balancing my exposure for the ambient when I could. But there was a particular spot in the club where there were three spots pointed at a mirrored pillar. The spots created excellent lighting, so I didn’t need my flashes. The color temperature was perfect, and the quality of light, although hard, worked with the scene. An added benefit of using the ambient light was the ability to include a more interesting background, because I was able to use a higher ISO, slower shutter speed, and larger aperture. You can see sparkling strings and the tables in the background, and you can even see glints of purple in the column.
So, if you want absolute control over your light, use flash. But, if you are capturing the environment or the lighting is already just right, use the ambient light already available to you.