What batteries

[Gulliver911]

Using a Canon Speedlight430EX; and very annoyed at the time it takes for the flash to be ready when I power it on. The red light comes after 30 seconds or more.

Any advise as to what batteries to use to get the flash ready quicker ?

Thanks

[matthew_h]

Cheapest option is to get hold of some high power rechargable AA batteries.

I've got a load of 2600mAh ones from ebay along with a quick charger. You get ones with even more oomph now though. Basically, the higher the mAh value the more power they can kick out and for longer.

[Gulliver911]

matthew_h said:

Cheapest option is to get hold of some high power rechargable AA batteries.

I've got a load of 2600mAh ones from ebay along with a quick charger. You get ones with even more oomph now though. Basically, the higher the mAh value the more power they can kick out and for longer.

So the mAh value condition how quickly the flash can ramp up ?

[matthew_h]

Yup, it seems to. Sticking them in makes my flash recylce far quicker than with even fresh Duracells in. They last longer before they go off too.

[stuart b]

mAh is "milliamp hours" which is strictly a measure of the capacity of the battery, not its "power" (i.e. ability to charge a flash more quickly). More mAh means they last longer.

Matthew h - I'm not disagreeing with you if you say that in practice they also charge the flash faster. I have no experience of that. Just clarifying what mAh means. It could well be that higher capacity batteries somehow have an ability to deliver more current more quickly - I'll give it a try next time I'm replacing mine.

Cheers
Stuart

[_dobbo_]

stuart b said:

mAh is "milliamp hours" which is strictly a measure of the capacity of the battery, not its "power" (i.e. ability to charge a flash more quickly). More mAh means they last longer.

Matthew h - I'm not disagreeing with you if you say that in practice they also charge the flash faster. I have no experience of that. Just clarifying what mAh means. It could well be that higher capacity batteries somehow have an ability to deliver more current more quickly - I'll give it a try next time I'm replacing mine.

Cheers
Stuart

Possibility that I'm being thick is high, but..... Isn't mAh a combination of both capacity and current draw? ie a 2500mAh battery can provide 2500 milliamps for one hour, whilst a 2700mAh batter can provide 2700 for one hour, thus greater current draw, and faster flash recycling?

[Gemm]

Apparently Lithium batteries have better recycling time but I've never tried them. I use rechargeables (2300mAh) and it takes around 5 secs to charge the flash.

[Ian_H]

The rechargeable batteries definitely refresh the flash faster and if you use 12 in conjunction with the Canon battery holder they recharge the flash instantly for a looooong time

[twister]

_dobbo_ said:

Possibility that I'm being thick is high, but..... Isn't mAh a combination of both capacity and current draw? ie a 2500mAh battery can provide 2500 milliamps for one hour, whilst a 2700mAh batter can provide 2700 for one hour, thus greater current draw, and faster flash recycling?

Not quite - the mAh rating is an indication of how much energy is stored in the battery, but the rate at which you can extract it depends on the internal resistance of the battery and the battery voltage (I = V/R). For two batteries with essentially the same internal structure/chemistry (e.g. two NiMH batteries of 2500 and 2700mAh ratings respectively) they will both be able to deliver the same current to begin with, but the 2700-rated battery will give you a little bit more runtime at that current.

[Gulliver911]

From a Cononn site on Flash photography, it looks like rechargeable NiMh or NiCad have the best ramp up time to get the flash up and ready:

Standard AA non-alkaline (zinc carbon) cells.


Pros: Available for next to nothing.

Cons: Don’t last very long at all and can’t be recharged. They also have fairly high internal resistance and so it takes a few extra seconds for the flash unit to recharge between shots.

Standard AA alkaline cells.


Pros: Alkalines are cheaply and readily available anywhere. They store a fair bit of power and let you go a reasonably long time between replacements.

Cons: Last much longer than carbon zinc cells but otherwise have the same disadvantages. Recycle time to full power can range from 6-20 seconds, depending on how new the cells are.

Rechargeable nickel-cadmium (NiCad) cells.


Pros: Relatively inexpensive, rechargeable hundreds of times. They have a fairly low internal resistance and so decrease the recycle time the flash unit will take to recharge to full power to 4-6 seconds. NiCads also have better cold-weather performance than alkalines - their performance suffers when the temperature drops below freezing, but not as badly.

Cons: Don’t store as much juice as alkalines, so you have to switch batteries much more often. NiCad cells are also hazardous household waste (heavy metals) and should not be thrown into the regular garbage system. NiCad cells drain flat (“self-discharge” within a few weeks after charging.


Lithium AA (FR6) cells.


Pros: A fairly new development, these are lithium cells built to an AA shape. They store a lot of power, have long shelf lives, and recharge the flash at roughly the same rate as alkalines.

Cons: Really expensive and not rechargeable. Steep death curves - they’ll work fine and then suddenly run out of power unexpectedly. Most importantly, only the latest Canon Speedlites can use them. Older models are not compatible with lithium AA cells owing to power issues, and might be damaged by them. The 540EZ and all EX series flash units can safely use lithium cells; all other flash units cannot.

Rechargeable nickel metal hydride (NiMH) cells.


Pros: Affordable and rechargeable hundreds of times. Higher capacity (1600 mAH and up) cells have similar capacities to alkaline cells. Not as hazardous to the environment as NiCads. Have a similar recycle time to full charge as NiCads - around 4-6 seconds. Personally I think NiMHs are the best AA battery technology around when you factor in cost and performance issues.

Cons: Require different chargers from commonly available NiCad chargers. Supposedly can self-discharge in a couple of weeks, but I’ve never had a problem with this.

[poah]

I use 7dayshop own brans 2600mAh NiMH ones

[sidaorb]

Have been using Duracell Nimh 2500mah for about a year, great batteries. Often in either Boots or Argos at silly money.

Carl

[twister]

poah said:

I use 7dayshop own brans 2600mAh NiMH ones

Another vote for 7dayshop here, using their 2700 and 2800mAh AAs here, and they just seem to go on and on and on, long after the point where I'm expecting to have to have changed to a fresh set already. Prices are stupidly low too (or is it that high street prices are stupidly high...)