With the Earth being 70% water there are a lot of beaches out there. Some are sandy and smooth, others rocky and full of edges. For our beach photography basics lesson we'll focus on sandy beaches as they present the most unique challenges to getting a great beach picture. There are 3 main points to remember when working with beaches. These are protecting your camera, exposure, and horizons.
Dealing with Sand and Water
Before we get into how to actually take the picture we need to discuss protecting your camera from the sand and water. Sand inside your camera won't just cause spots on the picture, it will wear down the moving parts of your camera like the focus ring of your lens. Water will spot your lens and if it gets in the electronics it will produce shorts that are likely to destroy the camera.
To protect your camera try to avoid windy days when surf and sand are flying, and consider a protective housing on your camera such as a rain hood. You can purchase a rain hood or make your own out of a large plastic bag. This won't create a perfect line of protection for your camera but it will greatly reduce the chances of sand/water damage.
Most of the time, your camera will try to underexpose a beach scene due to bright glare from water or bright sand. Remember, your camera's exposure meter wants everything to be an even grey. To combat this, bracket a few exposures to see what works best for your particular lighting instance and then set your exposure compensation accordingly. Be aware that rapidly changing lighting situations (setting sun for example) will most likely require manual exposure settings rather than relying on the camera's computer.
Because many beach scenes have a wide expanses of horizon visible it is very important to make sure the horizon line is straight. Beyond practice, some cameras now come with built in levels to help you keep the horizon straight. You can also use a small pocket level from any hardware store if you are working with a tripod.