This video is a demonstration of partial heating with a Halogen Point Heater that blocks light with a frame.
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Partial heating on a piece of wood-star-shaped ★ 
Heating of wood series 1 – Spruce 
Heating of wood series 4 – Paulownia 
Heating of wood series 5 – Agathis 
Heating of wood series 3 – Japanese cypress 
Heating of wood series 2 – Japanese cedar Sugi 
Heating of wood series 7 – Balsa 
Heating control of the wood emits smoke