a little OT: sr44.com

Kat

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Jun 26, 2005
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Has anyone ever ordered from this site? I'm looking for cheaper sources of the battery for my RFs. Silver oxide batts don't seem to be available here in the Philippines.
 
I need them for a couple of cams I got that take in silver oxide--a Fujica ST705 and an Olympus XA3. I just got myself a light meter as well, but I have previously relied 100% on in-camera metering, and will probably continue to do so, I'm worried the alkalines' fluctuating voltage would affect readings...
 
Alkaline have a very different discharge curve from silver-oxide. Certain equipment only works reliably with SR44 and equivalents. And it's never a bad idea to use them even if the camera or meter is adjusted for alkaline. I never buy alkaline batteries in this form factor. Ever.
 
The way I understand it is this:

Both silver and alkaline cells are made in the same form factor, and lithium is also made in a "double-up" size. Silver comes first and holds the most charge; if you run your batteries flat by taking pictures, it is the best choice. Lithium has the longest storage life so if you take pictures occasionally, then it would be the most economical (with a caveat). Alkaline is somewhere in between in performance.

The problem with lithium is that it has poor performace in many cameras, or appears to run it down at an alarming rate. I would tend to stay clear of them, unless it is said by the camera manufacturer to be compatible.

I have been using alkaline in both 44 (aka 76, 13, etc) and the "four-up" 28 (aka 544) form factors, and have found no difference in exposure accuracy and other battery-powered functions. In fact, I make my own "four-up" batteries by stacking four of those button cells together which is a great money saver. I guess the main thing is "suck it and see", but of course YMMV.
 
Hi,
Silver cells do have a slightly higher capacity than alkalines but a more important property is the discharge curve. Silver cells have a flat discharge curve wheras the alkalines slope. With most cameras post the mercury era and especially those that take more than one cell, it is generally not a problem as the meter is either bridged or the is some form of compensation.

However if you are using these with diodes or a battery adapter to replace mercuries, it is important to use silver's. The diode fix works by using the forward bias of the diode to drop the voltage a fixed amount. With a silver cell in the adapter, you will get a constant 1.35v till almost battery exhaustion just like a mercury. With an alkaline, it will start at about 1.35 but drop to about 1.1v as the battery gets used which is likely to throw the meter out.

Kim
 
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