🚀 go-pugleaf

Henry Spencer (henry@zoo.toronto.edu) wrote:
: In article <2n5sa1$beu@vanbc.wimsey.com> mfraser@vanbc.wimsey.com (Mark Fraser) writes:
: >... I have often wondered about the CCD amateur astronomy
: >cameras.  A little bit of filtering, a little bit of tweaking, a little
: >bit of lens work, and presto.....

: If they're silicon CCDs, which I believe all of them are, forget it.
: Thermal-IR photons simply are not energetic enough to register on them.

Sure they are. The only problem is that you need fairly high temperatures. I have
a small monochrome CCD camera that will easily produce a picture of a hot 
soldering iron, etc, in a completely dark room, from the heat produced by the
iron. Admittedly, imaging at room temperature is more of a problem...
(he could always build a large fire inside his house, and look for heat leaks
from that ;-) )

As an aside, I have played with using the PIR detectors intended for intruder
alarms as sensors in a slow-scan imaging system, with fair results. The main
drawback is quite short range, ie a few meters or less.

Patrick.
-- 
The shortest distance between two points has not yet been built.

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