Battery life is a real challenge in digital photography mainly because LCD displays consume so much battery power and the camera's flash also makes heavy draws on it. Progress has been made however, and today's batteries are both longer lasting and more expensive than those of a few years ago. Many cameras will accept AA alkaline batteries, but they don't last long, especially on cold days when they may die almost immediately. No matter what battery type your camera uses, it's prudent to have more than one set so you can have a spare with you or can be charging one while using another. You may also want to consider an AC adapter so you can plug the camera into the wall. It limits your range but lets you keep shooting or sharing. Many cameras today require that you use special rechargeable Lithium Ion (Liion) batteries (sometimes called battery packs) but if your camera accepts AA batteries, you need rechargeable batteries and a battery charger. (In pinch you can use alkaline batteries should you find your rechargeables dead). By far the most popular AA rechargeable batteries are Nickel Metal Hydride (NiMH).These batteries are environmentally friendly because they are made from nontoxic metals. If they have any weakness, it's their overall life; lasting only about 400 charge and discharge cycles. Their power is rated in mAh (milliamp hours) and the higher it is the longer life it will have between charges. The longest lasting are now about 2700mAh. Digital cameras become nothing more than paper weights when their batteries run out. Most cameras don't give you a real-time status report on your remaining battery charge. At best they display icons that tell you when the batteries are fully charged and when they are almost depleted, but don't tell you much in between. The exception is Sony, whose infoLithium� batteries communicate their status to the camera so it can be displayed for you. You'll always know approximate how much time remains so you can plan ahead. There are ways to prolong your battery's charge. Here are some of them.

1. When you first get new batteries charge and discharge them a few times so they get fully charged.



2. When photographing, turn off the LCD monitor and use the optical viewfinder if your camera has one. It's better for taking pictures anyway. When you have to use the LCD monitor, turn down its brightness.



3. Occasionally clean the battery contacts in the camera and charger with a cotton swab and rubbing alcohol (isopropyl alcohol). Most charging problems are caused by dirty contacts on the battery or charger.



4. When not using the camera for an extended period, remove the battery and store it in a cool, dry place. (Also remove flash memory cards from the camera when not in use.) Some cameras draw a small current even when off.

Batteries don't last forever. Depending on their type, they'll last between 400-700 recharge cycles. For heavy users that's about 1 to 2 years. Generally, you can tell they are failing when they no longer hold as long a charge.

Most cameras have a second battery, sometimes called a clock battery, that lets the camera retain its memory when the main batteries are removed. This battery is recharged when you replace the main battery but if there is too long a period between removing the battery and replacing it, the clock battery may run out.