Recognizing where usable light exists in any scene is a necessary skill if you want to excel at photographing people.
Instead of dragging out a lot of lighting equipment, the more experienced photographers learn early on to assess where the ‘good usable light‘ is and try to work with it.
By goodusable light I mean light which you can use either to fill, highlight or accent your subject as opposed to the visible light which enables you to see or locate your lost contact lens.
The trouble is, that particular skill only comes after you begin playing with lighting your subjects using flash or strobes.
Assessing the Scene
Whenever I arrive at a location to shoot, I consider the following: backgrounds and light.
It’s a well known fact in photography that “whatever doesn’t add always distracts from your subject.”
If I can find a usable background or backdrop on location, it means one less thing to set up like a seamless or muslin and their accompanying stands.
Sometimes, there is just not enough time or space to be moving people and furniture around especially if there are multiple wardrobe changes.
Good Usable Light
Light has 3 components that matter for photographers: color temperature, quantity and quality.
If I step into a room with a lot of daylight streaming in and it is directional, that can be good ‘quality light‘ especially if the walls are neutral in color.
On the other hand if there is a lot of tungsten or incandescent mixed in with florescent and daylight, I have to decide which of these light sources I want to dominate and then gel my Speedlites or strobes to match them if I need to.
Too little light to autofocus
Worse case scenario, I can always bring in a continuous light source like a battery-operated small LED light panel to help me manually focus.
So my decision on where to shoot once I arrive is to find the best of both these two criteria: a good uncluttered or complementary background and an area where there is available light I can use.