Problem with Canon EOS 40D

[tomjenner]

I bought my Canon EOS 40D last June and I have been very happy with it, until recently I have been having some problems. Every now and again it cuts out and there is an error message on the screen telling me to switch it off and on or change the battery. Also the flash sometimes flicks up even though there is clearly plenty of light. I have tried changing the battery, but this still keeps happening.
One difficulty I have is that I bought it in Texas whilst moving home from El Salvador to Mongolia, so I will probably not be able to use the warranty or visit a decent camera repair shop.
Any advice or suggestions would be very welcome.

Tom

[Overread]

A few things come to mind

1) The battery could have warn down so that its now no longer able hold a charge for very long - hence the removal need.

2) It could also be that its internal meter for monitering its charge statis is out of sync - a full discharge followed by a full recharge would be the most likley way to fix this.

As for the flash are you shooting in auto modes or the more manual ones (av, tv, manual). The auto modes flash will open up if the camera thinks it needs it - but in the other modes it should only open up if you select it to.

[tomjenner]

Thanks for the suggestions. The flash often opens up when its in auto mode, but in situations where it is very bright and a flash is clearly not necessary, such as where it would otherwise be shooting 1000th of a second.
The fact that the problem occurs with two different batteries suggests that its not the batteries, but something in the camera itself. I will try leaving the camera on to discharge completely and see how that works.

Tom

[Overread]

hmm I have often used flash for fill light in bright conditions when shooting into a more shadowed subject - it could be that the camera is choosing to use flashfill as well for a darker centre/main subject

[Macswede]

[QUOTE
2) It could also be that its internal meter for monitering its charge statis is out of sync - a full discharge followed by a full recharge would be the most likley way to fix this.[/QUOTE]

How do you fully discharge a battery? I've got one for my 40D that charges and quickly and then runs down very quickly. This is a recent problem and I've had the battery for some time.

[Overread]

full discharge usually means just drain it out till it won't work in the appliance anymore - sometimes force the camera on till it won't even start up - then try a full recharge. There are some expensive recharging stations which can perform a battery reset (drain followed by recharge) for AA and similar batteries - I assume there might be similar for camera batteries.
However if a full discharge and recharge has not worked then chances are the battery has worn out and its time for a new one

[Macswede]

full discharge usually means just drain it out till it won't work in the appliance anymore - sometimes force the camera on till it won't even start up - then try a full recharge.
However if a full discharge and recharge has not worked then chances are the battery has worn out and its time for a new one

Thanks very much, Overread! I'll follow your advice and leave the battery in the camera, ignoring warnings that it's time to change the battery, till it won't work at all any more.

[Nikon Kid]

Thats interesting, How long would a battery normally last how many hours of work ?

or is it how long is a piece of string

[Overread]

I think most batteries have an estimated lifespan and a good recharge/distcharge pattern helps keep them going (though camera batteries are not too badly affected by partial charge discharge cycles) but yes at the end of the day some are going to fail early and some will last way beyond their expected lifespan.

[tomjenner]

I fully discharged one of my batteries and after recharging it again everything has been working properly, so that seems to have have solved my problem. The difficulty is that it takes so long to discharge because the camera switches itself off to save the battery. When I am next back in the UK I will ask around to see if there is anything that can do a battery discharge. Thanks for all your help.

Tom

[tdodd]

You should be able to play a slideshow of a couple of images, ad nauseum, until the battery dies. You can just leave the camera running and go and do something interesting while it drains.