If you rent a 4WD Jeep, there are dirt (often mud!) roads in Koke'e State Park (Waimea Canyon & surroundings) that go some awfully scenic locations; check with the park visitor center for info on road conditions and recommendations.
If you enjoy boating, there are two rivers on the island where one can rent kayaks and paddle in scenic surroundings for an hour or three. One is on the Hanalei River on the north shore, with a rental place along the river in Hanalei. The other is on the Wailua River (the one with the famous Fern Grotto, which IMHO is overrated) on the east coast. Local phone books should turn them up. There may be more; those are just the two I found. You can take a camera if you have it slung around your neck and are careful.
There's scads of great hiking trails around Koke'e State Park (the one with Waimea Canyon, an absolute must-see). The one that leaves from the end of the road (above the Kalalau Valley) is my favorite of the half-dozen or so I've been on.
The weather in the higher elevations (Koke'e State Park etc.) is iffy, often foggy in areas. If it's fogged in one day, the next might be much better, so keep trying. Maybe you can call the park visitor center each morning to ask what the current conditions are before you drive up there (though I haven't tried it; perhaps I should the next time I'm there).
I love Kauai - it's my favorite by far of the Hawaiian Islands. You're not going to find much in way of "urban" or "architectural" sights to phtograph, but the gorgeous landscapes will keep you busy.
Lisa
