the weather here is warm pretty much 365 days a year. summer is very hot in the valleys and cooler at the beach. summer (late June thru Sept) weather ranges from 70 degrees F at the beach to 115 degrees F in Palm Springs. winter (mid Nov thru early March) weather ranges from 60 degrees F at the beach to 75 degrees in the valleys.
Photo Equipment: lots of photo ops. depends on where you go, but you can plan to take lots of pics.
Camping/Beach/Outdoor Gear: the normal camping gear should be fine for camping in southern CA. most of the parks and lakes have camp sites which have the usual amenities (i.e., fire pit, flat area for a tent, nearby restrooms).
Bring any kind of clothing you would use to stay cool during the day and warm during the night. Don't forget a jacket, just in case of rain or cold weather.
Camping/Beach/Outdoor Gear: Bring a bathing suit, snorkling gear, anything you might use for camping/beach.
Sneakers. Swimsuit. No coats, sweaters or rain gear necessary, maybe a windbreaker for 50 degree nights.
Toiletries and Medical Supplies: Sunscreen. Sunglasses.