Glass windows and thermal views

[Rotareneg]

A bit of a nitpick: vehicle windows (and building windows in general) are transparent in thermal sights when they should be opaque:

[Grenny]

A bit of a nitpick: vehicle windows (and building windows in general) are transparent in thermal sights when they should be opaque:

Same with buildings...known issue?

[3instein]

IRL would you be able to see a heat signature of someone behind glass with a thermal camera?

Thanks,

Mick.

[Rotareneg]

Regular glass isn't transparent to thermal radiation, which is why thermal cameras use germanium or other IR transparent materials for lenses.

[Grenny]

IRL would you be able to see a heat signature of someone behind glass with a thermal camera?

Thanks,

Mick.

No

[Sean]

It depends on the IR range the camera works in, but the cameras I have used in the past show reflections in glass (even tile). The most recent cutting edge gen cameras combine IR and amplified light (starlight) into one image, I'm not sure what would happen there.

I believe there is another recent thread on this issue with more in depth explanations.

There is a open bug about this in bugzilla.

[Grenny]

As you said. For the most 1. and 2nd gen tis systems, which usually work in LWIR, you can't. If you combine LWIR MWIR SWIR and light amplification...then you can see a lot more...

[LunarMadness]

I know "3rd gen" thermal imagers are supposed to combine LWIR and MWIR, would that do the trick?

[Rotareneg]

MWIR is 3 to 8 nm, LWIR 8 to 15 nm. Soda glass is pretty much opaque above 3 nm, so that probably wouldn't help much. SWIR and NIR would do fine with regular glass.

[Volcano]

Well, the short answer is that it is a modeling and texture issue. Since the TIS is handled by texture, then that means that not all windows can be made opaque. An example of this is the latest buildings where the windows are transparent meshes and do not have a texture, therefore they cannot be made opaque in TIS.

The truck in the image is another story though, it does have a texture assigned to the window and we CAN make it opaque, but then there is the case that no other (or not many other) vehicles are like that. Then you factor in other considerations like type of sight, thickness of glass, etc and the long answer is that we just allow (most) windows to be uniform transparent in TIS at the moment.

At some point we do plan on improving the buildings so that their windows are opaque in TIS view, because this is very important in urban environment because, as we know, in SB right now you can spot a man behind a glass window on second floor of window at 4000m in thermal sight. Then after improving the building windows, we will likely carry it over to vehicles in the long term. One step at a time...

The point is, it's complicated.

[3instein]

Thanks for the answers guys,never really thought about it much but just assumed that you would see some kind of signature,live and learn,

Cheers,

Mick.