In a bowl, sift together the flour, baking powder, baking soda, salt and sugar. Add the dill and the shortening; blend unti lit resembles meal. Stir in sour cream and milk; stir until it just forms a soft sticky dough. Drop by rounded tablespoons onto a buttered baking sheet and bake in the middle of a prehated 425 oven for 15 to 17 minutes or until pale golden. Makes about 16 biscuits.