Normally, when you press the first gear of the exposure hand switch, the small green ring in the lower left corner of the display will be extinguished, about 0.5-1 seconds, you can continue to press the second gear, complete the exposure, and hear the prompt “beep”.
The way that affects the service life of the ball tube is the way that the first and second gears of the exposure hand switch are pressed.
From principle, the higher the temperature of the bulb, the shorter the life. When the first gear of the exposure hand switch is pressed, the DR device will immediately heat the bulb filament, heating the filament from a warm state to a hot state of about 2000 degrees. After the exposure, the filament temperature drops immediately to protect the filament.
The correct way to press the hand switch is: after the exposure green ring is lit, you can quickly, in 1-2 seconds time, one switch two consecutive times, complete the exposure, and can hear the exposure prompt sound.