Modern speedlights help us to bring light to our subjects in just about any environment. This technology is very much improved from the old flash bulb days and we can even use a variety of flash units off-camera and control them wirelessly.
The power and ease of use of these speedlights presents a dilemma of sorts: When shooting a subject should we use natural light or use these flash units?
I have to confess that I still prefer natural light whenever possible. I suppose part of the reason is that I am more comfortable with this since most of my photography uses natural light. Sometimes natural light is not available so it is a no-brainer that in these cases a speedlight needs to be used. But what about when this deciding factor is not so clear or when fill light could be helpful?
A photography could bounce natural light to be sure, and yet a speedlight can be adjusted precisely to provide just the amount of light you are looking to include in the photograph.
Natural light, especially in the golden hours, is hard to match or imitate. This is another reason why I prefer using natural light. However, there are times when this will not work for a variety of reasons. Maybe the natural light is quickly fading. Having a flash unit available in the camera bag is certainly a nice option.
I suggest that you experiment with all kinds of lighting. Recently our family was on vacation and of course I had my camera gear with me. Two nights, after the rest of the family went to bed, I stayed up in the living room of our hotel and experimented with my SB-900. I tried to bounce the light from all kinds of positions. This taught me a lot. Experimenting with light is something we all should do more often.