1. How far away can you be and still use the Milwaukee Thermal Imager?
To see a 1"x1" object and fill one pixel off the Thermal Imager - you can be 17 feet away. Or to see a 1'x1' object and fill one pixel off the Thermal Imager - you can be 200 feet away.
But practically speaking, we need to be close enough to fill the target on the display with the area of interest. So, it just depends.
You can easily be far enough back to get a Thermal Image of an entire house and then to move closer to investigate potential issues in more detail.