Re: gEDA-user: DIY thermographic camera?

[Kai-Martin Knaak <kmk@xxxxxxxxxxxxxxx>]

On Wed, 05 Nov 2008 10:01:37 -0500, Randall Nortman wrote:

> ould one get reasonably useful results from a hacked camcorder or
> digital camera with appropriate filters?

Short answer: No. 

Long version: The light detector in consumer camcorders and cameras is 
based on silicon. Sensitivity of silicon is fairly low for UV light, 
rises towards the red end of the spectrum. It peaks at 950 nm and drops 
like a rock when going further to the infrared. However, the wavelength 
of heat radiation of houses is an order of magnitude larger (about 
10 µm). The photo diode is essentially insensitive to this kind of 
radiation. 

---<(kaimartin)>---
-- 
Kai-Martin Knaak                                  tel: +49-511-762-2895
Universität Hannover, Inst. für Quantenoptik      fax: +49-511-762-2211	
Welfengarten 1, 30167 Hannover           http://www.iqo.uni-hannover.de
GPG key:    http://pgp.mit.edu:11371/pks/lookup?search=Knaak+kmk&op=get



_______________________________________________
geda-user mailing list
geda-user@xxxxxxxxxxxxxx
http://www.seul.org/cgi-bin/mailman/listinfo/geda-user