550EX without Batteries

[bob_krueger]

I have a 550EX flash unit that I rarely use, since the main thing I

shoot is motorsports. Although I use lithium AA batteries in it, it

would probably still be best if I removed them until I need to use

the flash. I have two custom functions set...second curtain sync.

and disabling of the modeling flash. I have checked the manual

and I can't find anything that answers my question, which is...

 

Are the custom functions persistent or volatile? When battery

power is removed from the flash, will they reset to their default

values?

[dfdncithekxlbn8kaglf33]

They will reset to the defaults each time. I store mine without batteries and just do a routine when I load them in that sets my pref on the unit and head out...

[bill_goldman]

I have 3 550EX Speedlites and always store them without the batteries. I find they will retain the custom function settings indefinitely without batteries but believe they may not if the power switch is turned on, although I haven's tried it. Other settings, such as High Speed Sync are retained at least long enough to change batteries.

 

Since my response contradicts the previous post, why not try it yourself and see which is correct?

[alexander_trace]

My 550EX also retains the only custom function I have (disabling modeling flash) when I remove the batteries. So now you have 2 posts that agree!

 

Alex

[bob_krueger]

Well, two out of three ain't bad, so if you guys are willing to risk the loss of your custom functions, why shouldn't I gut it out too, right?

 

So I'll take out the batteries and then put them back in a month or so and let you all know who was right. It isn't exactly like having to reset all of the preferences in a computer system from scratch or something anyway, and there's less risk in losing the CFs than having the batteries leak in the unit, however unlikely that may be.

 

Thanks for the help.