Re: Opinions on a camera.

On Sat, 07 Apr 2007 14:15:39 +0100, Rob Morley wrote:

In article <2lMRh.8809$cj.7687@xxxxxxxxxxxxxxxxxxxx>, Fat Sam
samandjanetknox@xxxxxxxxxx says...

Aaaah. I would never have realised that the makeup of a battery could affect
the workings of the device it's powering.

It can be quite a problme with older equipment that used mercury cells -
these are now banned. They were used because they gave a very flat
voltage throughout their life, so there was no need for compensation
circuitry. The problem is that they were 1.35V - using a 1.5V cell will
tend to skew readings. Also alkaline cells lose voltage throughout their
life - silver oxide is better but runs at 1.55V. I recently bought an
old mechanical Praktica that has TTL metering, and I'm going to try
using a silver oxide cell with a diode to restrict the voltage, but with
a fully mechanical camera it's not that much of a problem - I can always
use a hand-held meter or just compensate a couple of stops for the
skewed reading.

I recall having done some web searches last year - there is a company in
Britain (as I recall) that has 'adapters' for the alkaline cells - it
seems they also control the output voltage and greatly extend the life,
though I don't recall if it was indicated to be as good as the original
mercury cells. There may be adapters to replace silver oxide too, I didn't
check that - I was looking for something to use in my Minolta SRT202 -
early 1970's vintage.


It's in the post to me now, so as soon as it arrives, I'll naturally be
heading straight out on a shooting spree, so I'll be sure to share the
results (so long as they're not too embarasing lol).

A couple of things to note with SLRs - when the lens is off never touch
the mirror or focussing screen, and when there's a film loaded do use
the body cap or lens cap to stop light leakage if you're not carrying
the camera in a closed case[1].

[1] I don't know how much of a problem this is with newer/better
cameras, but it could be a problem with older/cheaper ones.

.

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