An easier way from an electrical standpoint would be to take an auto lighter connection and hook it to a motorcycle battery. On a bike trailer it may work, but it would weigh a ton. I could almost carry a small generator for that weight and get electric lights for my trouble. Could be why the electric car is still more talk than go. Yet with the brain power on the list, maybe someone has a brilliant idea no one has ever tried.
-------- Original Message --------
Subject: Re: Recharging digital camera batteries
From: Bob <w8imo@xxxxxxxx>
Date: Thu, April 16, 2009 7:04 pm
To: List for Photo/Imaging Educators - Professionals - Students
<photoforum@xxxxxxxxxxxxxxxxxx>
I'm not sure if you want to put a 9V battery directly to a BP511, I hope not, You need some sort of charging circuit.
Doing some checking, I think you'd have to carry a lot of the 9V batteries. The typical 9V battery has a capacity of 500mAh while a BP511 has capacities from 1350-1500mAh. As the battery becomes depleted the voltage drops. As the voltage drops recharging sort of stops when the input voltage comes closer to the battery being charged. So you'd have to parallel three or four 9V to get charging capacity for the lithium ion BP511.
One exception was the Mercury cells that were a constant 1.35V from start to finish, a characteristic that made them ideal for metering in the old film cameras like my OM-1.
This has been an interesting thread.
Bob
mark@xxxxxxxxxxxxxxxxxxxx wrote:Well there are some good ideas. I always carry 3 batteries, but one never knows just how fast one is going to go through them and when one is going to decide to up and quit. Staying out for as much as a week needing 3 batteries per day would be tough.
I don't know if the simple light weight 9 volt battery, the type that used to be used in radios before Ipods would work. Light, may not last that long, but a 9 volt is a couple of bucks. Best Buy had the batteries for about $40 bucks or so. Yes I can get them cheaper, but I am not going to get them $2 cheap and if that $2 will charge a $40 buck battery all the better.
The back packs with the solar cells look interesting and could be a solution for a laptop battery, but its also a lot more than I wanted to spend at this point. I bought two 4 gig CF flash cards at Costco last week for about 35 bucks. Extra cards for me would make more sense than trying to deal with an image dump till I can get to power for the laptop.
I did see what looked like a grip for the body on KEH that took AA batteries. The AA might solve the problem if a set of batteries would last as long as a battery pack. Again that was also a couple of hundred bucks, but I would at least get the verticle shutter release back.
-------- Original Message --------
Subject: Re: Recharging digital camera batteries
From: Bob <w8imo@xxxxxxxx>
Date: Wed, April 15, 2009 9:20 pm
To: List for Photo/Imaging Educators - Professionals - Students
<photoforum@xxxxxxxxxxxxxxxxxx>
I'm curious, what voltage batteries do they charge and how small do they fold?
Bob
Emily L. Ferguson wrote:Rolled plastic solar chargers have been used on boats now for about 10 years. They're all over the web, just hunt them down.
-- ///// ( O O ) --------------------oOOO-----O----OOOo-----73 de w8imo@xxxxxxxx------ I plan to live forever. So far, so good......
-- ///// ( O O ) --------------------oOOO-----O----OOOo-----73 de w8imo@xxxxxxxx------ I plan to live forever. So far, so good......
