If the camera or flash is designed in such a way that the internal
resistance of the battery also limits the current, rather than the
impedance of the device alone, then a battery with lower internal
resistance could indeed lead to a larger current flowing through the
device. IMHO this is to be considered as bad design, but it was often
used in the past.
I think that this is the reason for the warning (or rather disclaimer,
I would call it). It is impossible to say if using NiMH cells could
indeed damage the camera or not.
Frank van Lindert
Utrecht nL.
Tue, 02 Dec 2008 07:41:39 -0500, Chuck Norcutt
<chucknorcutt@xxxxxxxxxxxxxxxx> wrote:
>A friend just purchased an old Ricoh FF-90 film P&S camera. He wants to
>use NiMH batteries but the user's manual (which can be found here)
><http://www.butkus.org/chinon/ricoh/ricoh_ff-90/ricoh_ff-90.htm> states:
>------------------------------------------------------------
>* Do not use Nickel Cadmium batteries. "Use of rechargeable Ni-cad
>batteries is not recommended. Due to higher internal amperage, the
>electronics in your Ricoh camera/flash unit may be damaged. If damage
>due to use of Ni-cad batteries occurs, the warranty will be considered
>null and void"
>------------------------------------------------------------
>
>Can someone explain why this is? I can understand problems with NiCad
>or NiMH possibly not delivering enough voltage for proper operation but
>I don't understand just the *capability* of the batteries to deliver a
>higher current as injurious. In fact, my limited knowledge of
>electronics (Ohm's law: I=V/R) would say that the fixed resistance of
>the camera's circuits would cause a lower current draw with lower
>voltage batteries. Without understanding why I suspect that the flash
>is the problem since the flash, during recharge, is that only thing that
>normally draws a high current. If that's the case could NiMH be used if
>the flash is turned off?
>
>Thanks,
>Chuck Norcutt
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