Hi Tal,
thank you for show the problem.
I tried to found a problem with the Box measurement but it work like expected. But after change from Thermal Expert to Seek thermal XR i found the problem.
Its not the Measurement, its the image aquisition from the Seek.
You can see this a better way:
1. set a measurement Point (middle mouse klick)
2. by default the 3x3Kernel is active.
(that means the center pixel and all neighbours are merged to the result value)
3. doubble click on the Spot and go to the "Meas Grid"
4. disable the "Kernel 3x3"
5. enable the "Show Raw"
Now you have a single spot (pixel) Value and see the Raw Ushort Value and the calculated temperature.
By moving somwere outside of the area with the Spot, you will see the Raw value is shifting relative to the rest of the image.
i need to look where the problem is...