[Phys-L] Absorption and Scattering of IR By CO2 Gas

["Zani, Gerald" <gerald_zani@brown.edu>]

Dear Tap-l,

We have a FLIR IR thermal camera and want to use it to show that CO2 gas
absorbs IR.

Does anyone do this?
How?

For our demo, we made a tank and filled it with CO2 gas, as shown in this
video:
https://www.youtube.com/watch?v=Ot5n9m4whaw&ab_channel=m1der1

But we are having a problem.

It might be due to the default setting for the thermal camera, which is for
automatic thermal tuning?
If So, then when the image gets dimmer due to the IR light scattering by
the CO2 gas, the camera is automatically tuning the thermal span and the
thermal level. This defeats the demo. It appears that the CO2 is not
scattering the light.

To prevent this problem, we must go into the camera menu to adjust the
brightness of a FLIR thermal camera so it has a manual setting, not
automatic and we need to find the thermal cameras Temperature Scale
settings, which have a span and a level.

We need to change the temperature scale, the temperature span and the
temperature level. This process is called thermal tuning.

Does anyone know how to do this?

Thanks,
- JZ

-- 
Gerald Zani
Senior Engineering Technician
Brown University School of Engineering
(401) 863-9571