This may be of interest to some digest members.
The F5 has a computer inside, as do many sophisticated slr cameras.
When you turn on the power switch, the computer boots up and begins
working. It constantly checks each and every switch on the body - the
af/shutter release switch, control knob switches, and many other electronic
subsystems - to sense user actions - changes to any setting.
Leaving the manual power switch of any modern slr body 'on' will
inevitably result to a low but constant drain on the batteries. Pressing
the shutter release part-way down to activate the AF motor and light
sensing systems - or leaving the body in a permanent 'full on' mode - will
increase drain on the batteries significantly.
If you want the longest possible battery life, you should
understand that a great deal is happening inside the camera unless you use
the one switch that disconnects the battery from the body's electronics.
The same situation occurs with portable computers (and with any ac powered
desktop computer as well).
I often wish for a 'real' power switch for my Sharp electronic
organizer. The batteries are drained all the time because the 'off' button
does NOT disconnect the batteries from the computer.
This behavior is separate from any battery voltage monitoring issue
with the F5. I suspect that Nikon decided to make the F5 'failsafe',
setting the minimum allowable battery voltage a bit higher than the bare
minimum required, to guarantee that all features would continue to work at
factory specification or cause the F5 to 'stop working' if there was any
chance that the battery was close to the minimum required for top
performance. Sorry about that wordy sentence.
Nils Dahl
