Hey everyone. I have found these forums very helpful - so I though I'd post a detailed tutorial on how I connected a high capacity external battery to my DSLR (Nikon D300 - but a similar approach could be used for all DSLRs). I know its been done, but not with as much detail.

http://blurmediaphotography.blogspot.co ... lapse.html

Cheers

it is interesting that nikon doesn't have a slot for the ac cord - Canon has a nice little flap for the cord.

thanks for the tutorial

timt

Very cool, This could easily be adapted to use an external 12v battery using a dc-dc converter like this one http://www.mini-box.com/DCDC-USB
Sure beats buying canon's $180 adapter (for the LP-E6 battery) even the aftermarket ones are $120. You could use this with a standard wall charger (provided it has enough amperage) or almost any battery you can think of due to the 6-34v input.
Thanks for sharing

This sounds like a really good idea. A quick question: do you think this workflow would also work with cheaper battery packs that are often used in remote control cars (search "7.2V battery pack" in Amazon)? I have a 7.2V battery for my Sony A55. It seems that it would be easy to splice these batteries onto the sacrificial battery. And they are quite a bit cheaper than many camcorder batteries. But I'm not an expert in electrical things, and am not sure that these batteries are appropriate for a DSLR camera?

I use the 7.2 volt model car batteries to power the camera for long periods. Make sure you have the polarity right and use the special charger for them. I can shoot all night and recharge the battery in about the same time it takes to download the flash card (minutes).

As previously mentioned, yes you can use an RC car battery - as long as the voltage matches (use a voltmeter to check the polarity before you connect it to your camera). I like those mini-box dc-dc converters a lot! I didn't know of a source for such an animal or I would have considered it. Makes connecting to a car battery via the cigarette lighter or directly pretty easy. For my purposes, the high capacity camcorder battery has more than enough longevity and is much more portable than most 12v batteries.

On another note - In hindsight, I have found that my cameras are somewhat finicky with this setup. I have no idea why - because the principal of how it works is sound. On occasion they seem to think that the batteries are depleted really fast - other times they work all night. This was outside this winter, so moisture/cold may have something to do with it, but I'm not sure.

I use this one which is a lot cheaper

http://www.ebay.com/itm/DC-DC-Converter ... 3a6d2363e3