"charlie" writes:

You just point your remote control at the digital camera such as a
standard webcam or a standard cell phone camera and push the button.
It shows up on mine as a white light like an led light when looking
at the image on my viewer screen, yet when I point the remote at my
eyeball, I see nothing.

And I would want to this...why?

One thing I *have* used this for: determining what a film P&S camera is
focusing on. I have a Yashica T4 which has passive IR autofocus, and
it's described as "multi beam". If I aim the camera at a piece of white
paper that fills the field of view and press the shutter release, a beam
of IR light from the camera illuminates several places on the paper -
but I can't see the beam myself. A little B&W security video camera
aimed at the same paper shows clearly just where the IR beams are
hitting the paper.

Looking at the video output on a monitor, I can draw lines on the paper
that show the boundaries of where the IR focus beams hit. Then when I
look at those marks in the camera viewfinder, I can see where the
autofocus spots are relative to the viewfinder markings.

(It should *also* work to simply have the video camera look through the
camera viewfinder, and observe the IR directly. But I didn't try
that.)

Unfortunately, digital P&S camera mostly use the slower but cheaper
contrast-detection autofocus instead of IR autofocus.

Dave