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|Category:||Batteries and Chargers|
Camera Batteries and charging advice - There are many types of battery available for your camera, and choosing which one is best can sometimes be confusing, we've therefore prepared this guide to help you understand the options available.
The most commonly used battery types for cameras are as follows:
Typical uses: Compact cameras, SLR cameras with optional motordrive, flash units.
Unlike alkaline batteries the charge in these batteries slowly decreases if they are left unused for around a month. However, being rechargeable means you can top them up again, but be warned NiCds suffer from what is known as 'memory effect' where if you don't fully discharge the batteries before charging their capacity is reduced. Over time this makes them become gradually less powerful until they eventually become useless. There are chargers available that help prevent this problem by discharging the battery before commencing charging. These chargers are definitely worth the extra money as you will obtain better performance from your batteries.
Typical uses: Low power digital cameras, Compact cameras, SLR motordrives, Flash units.
Nickel-Metal Hydride (NiMH)
Typical uses: High power digital cameras, SLR camera motordrives, Flash units.
Typical uses: Compact cameras, SLR cameras, occasional use digital cameras.
Typical uses: Digital cameras
Typical uses: Digital cameras
As cameras became moredependent on batteries they needed more power and two batteries where used. Then when Lithium arrived these two batteries werecombined to make a 3v version (shown above right). These offer much more power than the individual 1.5v silver oxides so last longer and are still used in cameras such as the Olympus OM-4ti and recently launched Nikon FM3A.
Batteries are a less important consideration in conventional film cameras, because they last for much longer without needing replacement. In digital cameras they can affect your buying decision. Althoughmany people would prefer to use standard types of batteries, such as AA's, most manufacturers develop their cameras around proprietary Li-ion batteries because of advantages listed earlier. Although in most cases they give very good performance they have the disadvantage of being expensive to replace or buy spares. So if you are thinking of purchasing a digital camera, consider these options, if you have a lot of AA rechargeables already, you might want to save money by buying an AA compatible camera. If however you want light, longer lasting power and are not to concerned about the expense, you should consider a camera using proprietary Li-ion batteries.
For an example of the differences in cost of ownership for these two types of battery, we looked at the Minolta Dimage 7 and the Sony DSC-F707. The Minolta uses 4xAA batteries, and is supplied with one set and a charger. The Sony uses their own Li-ion battery. Despite similarities in features, the difference in power use between the two cameras is substantial, with users reporting the Sony can last as long as three hours from one charge, yet Minolta users are quoting figures of only about an hour from each set of batteries. To achieve the same amount of camera usage as the Sony, a Minolta user would need to buy, charge and carry with them two more sets of high capacity NiMH batteries.
NiCd batteries can suffer from what is known as 'memory effect'. This is caused by the battery being only partially emptied of charge before being recharged. When it's next used it thinks it has less capacity than it does and causes reduced battery performance. NiMH batteries are not supposed to have this problem, but some people still insist they do.
Batteries should be properly conditioned before being used, this involves fully charging and discharging them for the first couple of cycles. It is therefore best to buy one of the more advanced chargers that can discharge the battery before charging it. This makes sure that no 'memory effect' can occur. The advanced chargers can also offer other useful features, like top-up charging where the batteries charge is kept high if they are left in the charger for a long time.
No battery should be left charging for longer than recommended by the manufacturer, unless the charger has advertised functionality to switch off when the proper charge has been achieved. If batteries are left charging after the recommended time, they power capacity may be reduced, they could even set on fire or explode.