🚀 go-pugleaf

jack@robotics (replying to an earlier question) writes:
>>The second CCD camera question deals with the CCD's response to IR.
>>What is the response curve of a CCD camera?  How quickly does the CCD's
>>sensitivity taper off as the frequency of the light drops below visible
>>and into IR?   And how come I can see the IR on my monitor/view-finder?
>>(try pointing your TV remote at the cam-corder).  My potential application
>>is a pseudo-night-vision device.
>
>It depends on the CCD used, and the optical filters in front of it that
>make specific CCD elements sensitive to red, green, or blue. But as you've
>observed, they do see some IR. Your monitor displays this signal as
>visible image (TV remote IR LED's are actually pretty bright).
>...

Although this won't help you with your camcorder... It turns out that
most CCD chips have pretty good IR sensitivity.  A very good and very
cheap way to get an IR video camera is to buy a cheap B&W video camera,
open it up, and (carefully) remove the IR filter that was placed over
the CCD by the camera manufacturer.  We do this to record animal (blue
crab to be specific) behavior under IR illumination.  Like us, a lot of
animals are insensitive to IR.

-Dean
--
Dean Pentcheff  (Internet: dean2@tbone.biol.scarolina.edu) (803) 777-8998
Department of Biology, University of South Carolina, Columbia SC 29205