Going by my past experience I am not very good at getting theright yet. I am going to a football ball and would like to take pictures of couples and candid's of people having fun on the dance floor etc. There will not be great lighting and I am not very keen on my flash. Do I use my flash for the couples shots anyway and if so how does that affect my f settings? And drop the f for candid shots with no flash if people are at a distance because the flash is very bad at a distance?