Hello,
I feed my ducks twice a day, breakfast and dinner, at 7am and 7pm respectively. I have found that they are much more friendly when they are hungry. I also try to feed them by hand as much as I can, it brings them in real close. Close enough to grab one. The females tend to be more shy and keep their distance. Except for the oldest female, she wiggles away when I grab her, but she doesn't make much effort to avoid capture either.
Anyway, as best you can, take your time to feed them by hand and they will get used to you. I notice the difference after a few days of hand feeding versus just flinging their food into the yard to forage. Not sure if I will ever get the flock that docile that they will sit on my lap or pet them, but they quack when I call them and will approach to a few feet. The sound of the lid coming off their food container brings them running as well.
Be patient and enjoy,
Rich