This couple-friend of mine asked me to take some outdoor photos for them, most likely at a beach or open park. My main issue will be lighting because (1) we live in a sunny climate and (2) I only have a shoe-mounted flash (Nikon SB-600); no fancy lighting equipement. So I'm wondering if doing this shoot in the morning vs.afternoon, vs. early evening would help?? Any other tips? p.s. I have a Nikon D90 and I intend to use my 50/1.4 and 85/1.4.