AGC turning off automatic gain control Lepton 3.5

[mhparant]

I have purchased two Lepton 3.5 and purethermal 2 for detection in an art project.

I realize that on GetThermal the AGC is all grayed out. It seems I can't turn off the gain control.

The image gain compensation makes it close to impossible to detect moving people without a manual gain control.

How can I turn off the auto-gain control?
I see no documentation regarding this or extra coding.

Regards,