The condense trails you see some gifs of alpha- and beta(minus)- particles.
Its a thermo-electrical heat pump witch cools it down. It took a while to stabilize the temperature down to under -30°C and to find the proper vapor. Its 99,9% Isopropanol. My measurement system failed under -37°C. The room temperature was about 20°C. So delta °T max is around 60°C. In the red pictures i used a strong Laser to get a line just above the cool plate. Nice contrast, but not good for the eyes. so now I’m using blue leds. the overall Powerconsumption is about 120 Watts.
*can be used as a instant ice cubes machine! (:
Beta- (thin trails) and Alpha-Decays (thick trails):