On Sun, 08 Jul 2012 12:17:17 -0700, mike wrote:

On 7/8/2012 9:41 AM, Jim Yanik wrote:
What I would really like is a
pseudo color far-IR camera, so I can see how hot things are getting
when I use my hot air SMT desoldering gun.

Ummm... watch your attributions. I wrote the above.

I'm not optimistic about that.
I have a crude far-IR camera used by firemen to find people
in smokey buildings. It's not calibrated, but I find that
the emissivity
of stuff varies so widely that it's useless for determining
relative temps.

True. All of them have a calibration knob, mostly to compensate for
changes in ambient temperature.

If you aim a non-contact IR thermometer at a motorcycle
radiator, it reads reasonably accurately. Point it at the
aluminum cylinder and it's WAY, WAY off.

Point it at a mirror and you get the temperature of whatever you see
in the mirror, not the temperature of the mirror. Yes, emissivity
matters.

I cobbled together a crude setup for reflowing nVidia chips
on laptops. Gave up completely on IR and went with thermocouples
for temp measurement.

Most of DVM's have thermocouple inputs. I got lucky and bought a
large box of pre-made thermocouples, in a variety of packages. I use
the tiny ones for spot temperatures. Still, it would be nice to have
a non-contact method that works.

In the past, I was working on converting a supermarket laser scanner
mechanism into a flying spot IR imager. I had something that sorta
worked but the response time was so slow, that is was nearly useless.
If I have time, I plan to continue as I now have a faster
microbolometer.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558