Re: [Leica] Batteries? Give me your experience.

["Henning J. Wulff" <henningw@archiphoto.com>]

At 10:23 PM -0500 2/9/00, MicroGrid@aol.com wrote:
>I responded a couple of weeks ago to a question about M6 battery life. Our
>company supplies a material to the advanced battery industry. We supply the
>cylindrical lithium battery market, (2/3 A cells, 1/3/N cells) - the M6
>batteries
>
>In my opinion the lithium cells are the best choice for powering the meter in
>an M6. Alkaline suffers greatly at low temps, and has a sloping discharge
>curve. Silver does not have the capacity. However you must keep in mind that;
>1, I have no experience with an M6, I still use an M5.
>2.A caveat, My company makes the mesh for the lithium cells we are talking
>about.
>
>I could give you the reasons in technical terms. Suffice it to say that the
>only practical objection I can find to using Li batteries when available, is
>the price.
>
>Having said that, there are so many complaints in this list of short life for
>Li batteries in M6's, there must be something more to it. Tom A's great
>suggestion about the check circuit during the last discussion of this subject
>shed some light on a potential repair solution. However even with that, there
>seems to be too many unhappy snappers out there for me.
>
>I will go the technical people at the big three makers of cylindrical lithium
>cells, Duracell, Matsushita, (Panasonic), and Sanyo, and ask for possible
>explanations for this phenomena. I am asking for some experiences, so I can
>put together a case study.
>
>Give me the details of your good and bad experiences. Classic, TTL,Switch
>on/off, Temperatures, etc. What about the SF20?
>If anyone knows what the mAh drain rates are or any other technical
>information on the M6, it would save me the trouble of finding it out from
>Leica.
>Please do not clog the list with this, Email me privately.
>Do not count on a quick response, I've got a job to do too. As I develop
>answers (or more questions) from the manufacturers I'll post them to the list.

My experiences:

Older, Wetzlar M6's - the lithiums do not have a straight drop-off of
energy, and the older M6 meter can't handle this gracefully. It will cause
you to start overexposing your shots near the end of its life. Use the
silver oxide cells.

Later Solms M6's - Lithiums or silver cells seem to work fine, but the
silver cells seem to last longer. There is still a slight chance of
overexposure near the end, so all in all, I still prefer the Ag cells.

TTL M6 - this one seems to respond to the use of Lithiums quite well, and
as it uses batteries at a faster rate, and lithiums are cheaper than a pair
of silver cells, I would use lithiums.

   *            Henning J. Wulff
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