I was playing with the idea of some kind of better controlled or robotized spot soldering with hot air.
It would be nice if the board and component temperature could be measured from a distance.
Found these sensors of Melexis MLX90614.
They can measure from -70 to 380 degrees Celsius.
Costs are (quantity=1)from about â‚¬12 (standard FieldOfView 90 degrees) to â‚¬40 (FOV 5 degrees) at Digikey.
Of course someone has done it already...