I have a digital camera for my time lapse photography project which I need to give extended battery life to. It will be a fixed installation with no access to main electricity.

Now I am thinking that I can use a 6 volt motorcycle battery to provide more working time. If I find a correct voltage unit I'm not going to damage the camera by it having a higher amp-hour battery am I?

If I understand batteries right they work on current draw and only supply on demand as it were.

I also thought that I could use a 6v solar charger to trickle charge the battery during the day and keep it going until the next day.
With the photograph intervals I want to use I wouldn't have to mess with the unit for about a month.

What do you think? Will it work?

[Edited on 9/7/08 by liam.mccaffrey]

Yep, should work just fine. Provided you're not taking a LOT of photos each day, and assuming the camera is a reasonably modern, low-draw unit, the solar charger would probably keep it topped up indefinitely. Most new cameras don't draw as much taking a few pics in a day as the common solar chargers produce in a day.

i take it there's no powersave function that turns it off after 5 mins of not bing used

That was my first thought too - all of my digital cameras revert to standby if left alone for a few minutes

yes, you are correct.

you would need to have a voltage regulator to supply the correct voltage, the camera itself will decide how much current it needs.

also you can have a solar charger but I am not sure tha complication is necessary.

I haven't done the sums but a motorcylce battery should be able to power you camera for a couple of days easily.

to save power it would be good idea to turn the lcd display off!!

.... but as ^^^^ say, if the camera has auto shutdown feature, and most do, then you are a bit stumped unless you take shots within that time.

The time lapse function on my camera works by turning the camera on and off as it needs to take the pictures, obviously there must be some kind of timer function going on inside the camera but this takes minimal power. I have used mine over a 24 hour period and the normal battery lasted!

Have you done any testing, the manual for my camera was like a bible and suggested how good the battery life will be, is there nothing in there to give you a rough idea?

Keep it simple.
I'm sure one of these would power the camera for about a year without any charging.
http://www.mdsbattery.co.uk/shop/productprofile.asp?ProductGroupID=540&ref=NP12-6

12000mA/ hours! Your average 4xAA camera batts are probably 2500 mA/hours. So thats 5 times the life with a continuous load, which your camera is not going to be...

when in timelapse mode my camera doesn't power down and i can turn the lcd off for more battery time

the unit would be fairly inaccessible so i would only want to mess with it when necessary

I made my first timelapse film last night, a hours worth of a pic a minute in my front room.
Came out really good!

This is going to be a fun project.

Thanks for all you help

Most lead-acid batteries will lose charge over a period of time, even if they're not used.

Maybe you'd be better of with some of those Uniross Hybrio rechargables - they claim to hold 80% of their charge over 12 months.

They do seem to be holding up well in my camera - I've had it a year and I've only charaged them once.