Of course I agree that aperture will be determined by GN and strobe to subject distance...
But strobe capability is told by WS.
Imagine you illuminate a group portrait, say 4m x 3m. If flash angle is narrower you will have to place it farther... So if placing the flashes at the distance that will cover all the group then what rules performance is WS.
Same with a softbox, GN is irrelevant, what counts is WS in that case.
Bookmarks