I know this is WAY OT but I need some clues to get started. I want to
use a digital camera as a security camera. The problem is that all
digital cameras that I know about turn themselves off automatically.
Turning them on takes too long; I want to disable the auto off or find a
simple camera that does not turn itself off. It will be powered from
the AC mains so battery life is a non-issue.

The best I've found so far is a game camera, which turns itself on when
it senses a hot animal and takes a picture. Unfortunately it takes
about 5 seconds to turn on, and 5 seconds seems like eternity in some
situations. I want instant pictures. I also would like to take pictures
from an external trigger signal.

It would be a lot easier in a film camera, but the hassle and time
delays (and cost) of developing film makes film impractical.

Any clue where to find such a camera or to find someone who knows how to
modify one?

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