On 20 Sep 2004 at 14:22, Malcolm Stewart wrote:
> ----- Original Message -----
> From: "Willem-Jan Markerink" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Monday, September 20, 2004 11:34 AM
> Subject: RE: EOS 1Ds mark ll ?
>
>
> > On 20 Sep 2004 at 17:04, Sinha, Shashvat wrote:
>
> > > Operating range 0-45C.
>
> > Wonder when/whether it will ever get the same -20C spec's as analog
> > bodies....
>
> I used to work in defence avionics, and our biggest challenge was to get
> electronic circuits to start up again after being "cold-soaked" overnight or
> longer at -50degC. Generally there was no problem if the equipment was left
> on as there was enough warmth to keep the transistors at a comfortable
> temperature. But, get the whole item really cold, and the transistor gain
> drops leading to a reluctance for oscillators to start - without which
> there's no clock to time the computer's CPU etc. Our problems used to start
> at around 0deg C - I'd expect modern transistors to have improved a little,
> but the laws of physics are quite difficult to beat!
But the odd thing is: when confronting experts from Canon with this
contrast between analog & digital, they gave me many samples of
arctic expeditions, where -20C apparently wasn't any problem.
So even poor cold-performance of the Li-ion batteries can't be an
argument (nothing beats NiCd on that aspect)....what's left is
probably a bunch of chickens afraid of the legal implications from a
guaranteed frost-level....
--
Bye,
Willem-Jan Markerink
The desire to understand
is sometimes far less intelligent than
the inability to understand
<[EMAIL PROTECTED]>
[note: 'a-one' & 'en-el'!]
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