580ex and battery life

[Amature]

Just purchased a Canon 580ex. This is my first flash unit purchase so excuse my ignorance. I am using Energizer 2500 mAh rechargable batteries.

How many flashes should be expected before having to recharge the batteries?

[scottbergerphoto]

It really depends on the ISO you are using and how often you max out the flash by working at the distance limits of the flash and ISO. On average, I think you should easily get 100 shots per set of four 2500Mah batteries. I usually carry 4 in the flash and 16 ready to go in a small zip case.

[Curtis N]

The instruction manual on the 580EX says approx. 100-700 flashes with 4 AA alkaline batteries. I think good NiMH batteries will do significantly better than this.

[Amature]

Thanks for the responses. It appears I have a problem then. Brand new batteries purchased Saturday 11/11/06. I am getting approx 12 flashes on the unit before they need recharging. My charger seems to be working ok because when I put the batteries in to charge I get a red charging lite, then after approx. 4 hours the lite goes out. So it seems like they are charging. Will need to further investigate either the charger or the batteries.

[Wilt]

Batteries usually need a few cycles of charge-discharge in order to reach full rated capacity.

Battery chargers typically change to 'charged' light too soon, and batteries will benefit from additional time on the charger in getting 'topped off'.

[Curtis N]

Yeah that doesn't sound right. You may want to try a set of alkalines and see what you get. If the alkalines work ok, then there's a problem with your other batteries or the charger.

Wilt's comments are generally correct, but you should still get a lot more than 12 flashes, even on a battery that's only half charged.