Her’s another post on the same subject.. flash. And why to use it.
The big reason, as you know if you have been reading here, is to be able to balance foreground and background. As in this combination of “no flash” – “flash” pictures of new model Khoral, whose personality will see her go far.
No flash gives you this:
While flash allows you to darken the background (ISO-Aperture-Shutter – The Triangle) while lighting up the subject with flash, which then gives you this:
But look closer. The other reason, the other difference you see: with directed light – your own light – you can shape. Legs look round, not flat. Faces look three-dimensional. Character comes out. I can light up certain parts (the person) and not other parts (the fence). Flash gives you power to create, rather than just power to reflect what is there.