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View Full Version : lithium ion equiv. AAs

t5Nitro
02/09/2009, 09:52 PM
I'm assuming everyone with an external flash is using lithium ion equivalent double As?

I'm just wondering on average how long they normally last?
TitusvileSurfer
02/09/2009, 11:32 PM
It depends on how you use your flash. f/8 ISO 100 is going to smoke your batteries compared to f/4 ISO 400. This makes a so called miles-per-gallon stamp very difficult. You can put your pedal to the metal and get crappy gas mileage or coast in idol all day and get great mileage.

As a general rule, I would say....long enough to worry about it just a little bit more than your camera itself.

1/60 shutter speed and 1/250 shutter speed, all else equal, with drain your batteries at the same rate.
JeffReef
02/09/2009, 11:45 PM
Are you talking about the Energizer Lithium? If so, that is different from Lithium Ion which has a nominal voltage of 3.7 volts per cell. Ordinary flash only uses (4) 1.2 - 1.5v AAs for a combined total of 4.8-6volts.

I just use the rechargable 2500mah AAs on my flash and it last for about 150 shots before the battery needs another charging.
louist
02/10/2009, 01:07 AM
I use Energiser's 2500mAh rechargeables.

A set of 4xAA's will last nearly a whole night of heavy shooting with bounce flash on a Canon 580ex with ISO400 and average aperture of f3.5-5.6. (approx 200 photos).

They will last quite a while, such that you won't need to worry about it. 2 sets of fully charged ones will take care of most flash needs.

Lithium Ions are not economical for external flash. Good rechargeable batteries provide excellent performance already. If you have deep and dark desires to induce epileptic seizure in all bystanders, you can always add a battery pack to the external flash.
Dino
02/10/2009, 05:55 AM
:) Buy yourself a set of eneloops, many places sell them (I hear Costco often has very good deals on sets of them, as well as Amazon). They're some of the best rechargeable batteries you can find. After you get the eneloops, buy a La Crosse charger to charge them (the batteries should come with a charger, but the La Crosse is a much better charger if you're using them extensively).