When shooting outdoors, we have less control. Depending on the situation we often have no idea what the conditions may be. Overcast days can provide good conditions for an outdoor portrait, but direct sun can create harsh shadows across the subject.
I have found, to my surprise, that most of my clients are requesting outdoor portraits, rather than indoor, studio portraits. So I've been spending more time trying to perfect my outdoor portraits technique.
These diffusers come in a various sizes and densities. For couples and small groups, large diffusers held up by stands can be used. This picture was captured in full sun, using a 22-inch hand-held Photoflex diffuser. An SB-800 was used for fill in TTL-BL-FP mode:
A 22-inch diffusers collapses quite small, and be carried in your pack, or attached on the outside of the pack or belt. Even for family, vacation photos, this small, inexpensive device can make a big improvement in your outdoor photos.