South Koreans demonstrating outside the Reckitt Benckiser headquaters in the UK.
Old fashioned portraits used to be very formal and the subjects typically defensive and cautious of displaying any emotion or expression, sometimes they just look really annoyed. Not smiling was attributed to being of upper-class society.
In a letter to the Sacramento Daily Union, Mark Twain wrote, “A photograph is a most important document, and there is nothing more damning to go down to posterity than a silly, foolish smile caught and fixed forever.”
That said, it really depends on the mood and looks you are going for but don’t panic if you are not sure. I got your back! Also, I do not ask for cheesy smiles and have captured wonderful shots of subjects smiling and laughing naturally.